Tracking China’s Increased Military Activities in the Indo-Pacific in 2025

By: Bonny Lin, Brian Hart, Leon Li, Truly Tinsley

February 5, 2026

China is rapidly modernizing and building up its military and paramilitary forces, providing Beijing with greater capacity to challenge and intimidate its neighbors. This report leverages open-source data to analyze observable trends in People's Liberation Army (PLA) activities in 2025 with a focus on key developments in the Indo-Pacific region.

Key Takeaways

Overall: In 2025, China's military activity increased in the Taiwan Strait, South China Sea, near Japan, and beyond the First Island Chain, reflecting an overall rise in operational tempo and geographic reach. Of the areas surveyed in this report, the only one to show a decrease in operational tempo is the China-Russia joint exercises.

• Taiwan Strait : In 2025, the PLA conducted a record-breaking level of air and maritime activity around Taiwan, sustaining the higher operational tempo of PLA activities that began following William Lai's inauguration as Taiwan's president in May 2024. This led to a marked increase in both average monthly PLA activities as well as a higher baseline of PLA activity. However, there was a minor year-over-year decrease in PLA activities in the latter portions of 2025, likely reflecting a temporary, tactical adjustment on China's end. In 2025, China also conducted two large-scale military exercises around Taiwan, named Strait Thunder-2025A and Justice Mission 2025.

• South China Sea : The PLA conducted a record 163 recorded operations in the South China Sea in 2025, including a record number of live-fire drills. China continued to harass its neighbors, especially the Philippines, but shifted its most aggressive actions away from Second Thomas Shoal toward Scarborough Shoal. The China Coast Guard (CCG) more than doubled its presence around Scarbough Shoal in 2025 compared to 2024.

• Japan and Its Surroundings : China continued to maintain pressure on Japan, and there was a spike of notable PLA escalatory moves in November and December. Throughout the year, there was a slight increase in the number of PLA naval vessels reported operating in the waters around Japan, though the average duration of each PLAN vessel's trip was shorter than in 2024. Similarly, there was an increase in the number of Chinese official ships within the contiguous zone of the disputed Senkaku/Diaoyu Islands, but a decrease in Chinese activity within the territorial seas there.

• Beyond the First Island Chain : The PLA ramped up its far-seas training and operations in 2025. China's navy conducted several unprecedented activities beyond the First Island Chain, including extensive voyages and live-fire drills around Australia and New Zealand, and simultaneous aircraft carrier operations in the Pacific for the first time. China's two operational aircraft carriers, Liaoning and Shandong, engaged in nearly twice as many days of operation beyond the first island chain in 2025 compared to 2024. China's coast guard also operated far into the Pacific.

• China-Russia Joint Military Exercises : China conducted six joint exercises with Russia in 2025-the lowest count since 2020 and down significantly from the all-time high of 14 in 2024. However, there were novel developments, most notably their first joint submarine patrol.

Taiwan

In 2025, four key trends emerged in the PLA's activities around Taiwan. First, there was more activity across the board in the air and maritime domains. Second, the PLA maintained a higher baseline of activity than before. Third, there was a slight year-over-year decrease in PLA activity in the latter part of the year from May to December 2025. Finally, the PLA continued the precedents set in recent years by conducting two large, named military exercises around Taiwan.

The PLA conducted a record level of overall activity around Taiwan in 2025. According to data from Taiwan's Ministry of National Defense (MND), PLA aircraft conducted 3,764 air incursions into Taiwan's de facto air defense identification zone (ADIZ), an increase of 22.4 percent from 2024 when the PLA smashed previous records.

A more nuanced analysis of the data reveals that 2025 was largely a continuation of trends that began in May 2024, when China ramped up pressure on Taiwan after the inauguration of Taiwan's President William Lai. Following Lai's inauguration address, the PLA conducted large-scale exercises around Taiwan named Joint Sword-2024A, and in October of that year, it staged Joint Sword-2024B exercises following Lai's National Day Speech. This contributed to a surge in activity that was largely sustained in 2025. From May 2024 to December 2025, average monthly PLA air incursions reached 319-a 129 percent increase from the monthly average from January 2022 to April 2024.

Chinese air activity not only increased overall, but the PLA also sustained a higher baseline of monthly activity. After May 2024, Chinese ADIZ incursions never dipped below 209 sorties per month, whereas before that, Chinese ADIZ incursions dipped as low as 64 sorties in one month (January 2024).

Similar trends are observable in the maritime domain. From May 2024 onwards, the average monthly reported number of naval vessels around Taiwan was 221. This is a 42 percent increase from the monthly average of 156 naval vessels from August 2022 to April 2024. The PLAN also operated a baseline of at least 190 vessels per month since May 2024, compared to the lowest number of 104 vessels in the previous period in 2022.

Starting in May 2024, the Taiwan MND began also reporting on the presence of "official ships" around Taiwan, which refer to China Coast Guard (CCG) ships or vessels from various law enforcement organizations like the Maritime Safety Administration (MSA). The average monthly reported numbers of CCG ships in 2024 and 2025 were both approximately 24 vessels.

It is worth noting, however, that there was a slight drop in operations in the latter part of 2025 compared to the same period in 2024. There were 2,479 total ADIZ incursions from May to December 2025, a 5.4 percent decrease from the same time the previous year. Similarly, from May to December 2025, there was a monthly average of 218 PLAN vessels, compared to 224 from May to December 2024, a 3 percent decrease. The available data on CCG ships also show a slight decrease in activity from May to December 2025 (178 ships) compared to the same period in 2024 (191 ships).

It is unclear what drove this plateau, but it does not undermine the overall annual increase in Chinese activities. This slight decrease is likely not a reflection of changes in China's overall goals towards the island or Chinese reassessments of its willingness to use coercive military means. It more likely represents a temporary and tactical readjustment in Chinese activities based on the dynamics among the United States, China, and Taiwan at that time. It could also reflect different PLA priorities, including a growing desire for the PLA to engage in more far-seas operations, or limitations in PLA bandwidth and capacity, given the massive purges within its senior ranks.

Following precedents set in recent years, the PLA conducted two large-scale drills and exercises around Taiwan in 2025, which saw major spikes in military activities. In April 2025, the PLA held the Strait Thunder-2025A drills near Taiwan, its outlying islands, and in Zhejiang Province. The two-day drills saw a total of 135 aircraft sorties (68 of which flew into Taiwan's de facto ADIZ) as well as a total of 38 PLA naval crafts around Taiwan. While significant, that is smaller compared to the recorded asset presence of other major exercises in the past. For instance, the Joint Sword-2024B exercise in October 2024 saw 153 aircraft sorties (111 of which intruded into Taiwan's ADIZ), and the April 2024 Joint Sword-2024A saw a combined 46 PLA naval vessels around Taiwan over two days.

The April Strait Thunder-2025A drills involved multiple discrete drills across different areas near Taiwan. The PLA Air Force conducted aircraft sorties west and south of Taiwan, and aircraft were launched from the Shandong aircraft carrier positioned east of Taiwan. The carrier strike group also conducted a series of drills, including joint ship-aircraft coordination, regional air dominance, and simulated sea and land strikes.

In Fujian and Zhejiang provinces, PLA ground forces conducted live-fire rocket drills, simulating strikes with 16 rocket launches against land targets that included targets resembling the Yongan LNG terminals in Kaohsiung, Taiwan. On the same day, four CCG patrol vessel formations patrolled in four areas surrounding Taiwan, while four other CCG vessels entered the waters of Matsu and Dongyu, Taiwan's outlying islands.

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The "A" designator in the name of the drills suggested that follow-up drills would come later in the year, and many speculated that China could hold another drill in October after President Lai's national day speech, as China did in the preceding year. However, no Strait Thunder-2025B drills occurred-likely due to a range of factors. This included the fact that President Lai omitted language from his address that Beijing has found most problematic in past speeches. This includes his assertion that China and Taiwan are "not subordinate to each other," a pronouncement that was also made by his predecessor, Tsai Ing-wen, since 2021.

In addition, from mid to late 2025, the Trump administration was cautious in its engagements with Taiwan. During this period, there was a relative plateau in PLA activity around the island. However, that relative calm was short-lived. In December, after the Trump administration approved a record $11.1 billion in arms sales to Taiwan, China escalated by launching the year's second major round of exercises around Taiwan, named Justice Mission-2025.

Carried out on December 29 and 30, the exercise simulated how China could blockade and encircle Taiwan. The PLA announced five large zones clustered around Taiwan's major maritime ports, especially Keelung in the north and Kaohsiung in the South. China's MSA also declared two additional zones, which further reduced the gaps in coverage around the island, and Taiwan's MND later reported that activities occurred in an eighth zone east of the island.

These collective exercise areas make Justice Mission 2025 the largest named Chinese exercise around Taiwan in recent years in terms of geographic reach. This large-scale exercise significantly impacted air traffic around Taiwan. According to Taiwan's Civil Aviation Administration, the exercise affected 857 international flights and cut off flights from the main island of Taiwan to Kinmen and Matsu.

These exercises also brought the PLA closer to Taiwan's shores than previous exercises. Several of the exercise zones intruded well into Taiwan's territorial waters (which extend out 12 nautical miles from Taiwan's claimed territorial baseline), bringing the PLA's live-fire naval drills closer to Taiwan than ever before. The PLA also reportedly conducted live-firing of rockets into Taiwan's contiguous zone, which extends 24 nautical miles out from Taiwan's territorial baseline. Taiwan's MND reported 27 rockets launched from China's Fujian Province landed in the waters north of Keelung, Taiwan, which was more than the 16 rocket launches reported during the Strait Thunder-2025A. The PLA Rocket Force (PLARF) also reportedly engaged in persistent tracking of high-value targets and simulated missile strikes against important military facilities in Taiwan.

At the same time, the exercises lacked some provocative actions seen in past exercises. Most notably, the PLARF did not fire ballistic missiles over the island as it did in August 2022, and the PLAN also did not deploy its aircraft carriers near the island. In place of full-size aircraft carriers, the PLA deployed a Type 075 amphibious assault ship, the Hainan, marking the first time such a vessel has been involved in a major exercise around Taiwan.

In all, the two-day exercises involved 207 total aircraft sorties (including 125 PLA air incursions into Taiwan's ADIZ), 31 PLAN vessels, and 16 official ships around Taiwan and its outlying islands. Compared to previous major exercises, this exercise had the largest total aircraft ADIZ incursions, though the Joint Sword-2024A had the largest total naval presence around Taiwan, at 46 vessels.

South China Sea

China has longstanding disputes and overlapping claims with several neighbors in the South China Sea, including Brunei, Indonesia, Malaysia, the Philippines, Taiwan, and Vietnam. For years, China has frequently deployed the PLA, CCG, various maritime law enforcement vessels, and maritime militia vessels to different areas to assert its claims and intimidate other countries. In 2025, China continued many of these activities, and the PLA increased its activities in the South China Sea.

China's most aggressive and high-profile activities in the South China Sea have been directed at the Philippines, a U.S. treaty ally. In the preceding years, tensions largely centered on the Second Thomas Shoal, where China's coast guard repeatedly blocked and harassed Philippine resupply missions to the grounded BRP Sierra Madre. Clashes there reached a peak in June 2024 when Chinese forces rammed and boarded a Philippine Navy inflatable boat and used knives and axes to damage the vessel. Weeks later in July, China and the Philippines reached an agreement to reduce tensions there.

In 2025, Second Thomas Shoal receded from the spotlight, and in its place, Scarborough Shoal returned to the center of China-Philippines tensions. There, the CCG repeatedly challenged and tried to expel Philippine vessels operating near the atoll. Analysis of ship-tracking data by the CSIS Asia Maritime Transparency Initiative shows that the CCG more than doubled its presence around Scarbough Shoal in 2025 compared to 2024. Tensions there particularly spiked in August when a confrontation resulted in a highly publicized collision between a Chinese Type 052D destroyer and a CCG cutter. Then, just days later, a PLA fighter "intercepted< /a>" a Philippine aircraft carrying journalists during a patrol flight over the shoal.

Looking beyond China's harassment of its neighbors, the PLA was highly active in the South China Sea in 2025. According to ChinaPower analysis of reports published by China's Maritime Safety Administration (MSA), the PLA conducted 163 different activities in the South China Sea, including live-firing activities, exercises and drills, training, military operations, and certain other activities.

This marks a record level of activity based on available reporting from the MSA, but it is worth noting that the MSA may not report every kind of activity. For instance, the Philippine Navy reported an overall Chinese presence of 286 military vessels in 2025 in the West Philippine Sea, but activities carried out by these vessels are not reported by the MSA. Looking in the specifics of the activities, it is also notable that the MSA reported 55 different PLA live-fire activities-up from the previous reported high of 47 in 2024.

Some of these activities are particularly notable. On February 21, 2025, China's MSA announced a live-fire military exercise in the Gulf of Tonkin on the same day Vietnam announced its new territorial water baseline in the gulf. On October 16, 2025, China announced an October 17 military training zone southwest of the Scarborough Shoal on the final day of the U.S.-Philippine Sama Sama naval exercises. Other activities reported by MSA include warnings of debris falling from orbital space launches. An increasing number of rocket debris zones appeared near Philippine waters, such as the November 28 announcement of debris from a Long March 7A rocket launch.

Japan and Its Surroundings

Another persistent flashpoint in the region is China-Japan relations. The two countries have often been embroiled in disputes and clashes, especially in the East China Sea. China-Japan relations suffered a major downturn starting in November 2025. In a Japanese Diet meeting, Sanae Takaichi, Japan's new prime minister, stated that a Chinese naval use of force against Taiwan could constitute a "survival-threatening situation" for Japan. China viewed her comments as highly provocative and interpreted them to mean that the Japan Self-Defense Forces would be legally allowed to engage in collective self-defense activities in the event of a conflict over Taiwan.

China escalated with a range of sharp diplomatic barbs, economic punishments, and significant but limited military operations against Japan. Days after Prime Minister Takaichi's comments, China's MSA announced multiple exercises in the Yellow Sea and near the disputed Senkaku/Diaoyu Islands. At one point, Japan scrambled jets after spotting a Chinese drone near Yonaguni Island, the closest Japanese island to Taiwan.

The following month saw follow-on Chinese military actions. In early December 2025, China deployed a large-scale maritime show of force, with over 100 naval and coast guard vessels sailing throughout the Yellow Sea, the East China Sea, the South China Sea, and the Taiwan Strait. On December 6, Chinese jet fighters took off from the patrolling Liaoning aircraft carrier and locked radars on Japanese fighter jets near the Okinawa Islands-a significant escalation. Three days later, China and Russia conducted a joint aerial patrol, flying their bombers over the Sea of Japan and through Japan's Okinawa main island and Miyako Island. This is the first time that Chinese and Russian bombers conducted a joint flight in the direction of Tokyo, and it was the first time since 2017 that Chinese bombers flew these routes.

Overall in 2025, public information showed a slight uptick in the total number of PLAN voyages near Japan compared to the prior year. PLA vessels conducted at least 111 voyages in waters near Japan in 2025-up slightly from 108 in 2024 and 106 in 2023. Of note, this included increased operations near Japan of China's more advanced and military capable naval vessels, including its aircraft carriers, cruisers, and destroyers.

Some of these involved increased Chinese operations near Japanese and U.S. bases. For example, in 2025, a record of at least 17 Chinese naval vessels transited the Osumi Strait, raising concerns in Tokyo that Beijing was conducting surveillance on a new Air Self-Defense Force base on Mageshima Island.

Although information published by Japan's Ministry of Defense (JMOD) suggests that the PLA engaged in more naval activities in 2025, the duration of published Chinese naval operations around Japan was shorter. In 2025, JMOD data indicates the presence of Chinese vessels in waters close to Japanese territories for a collective 302 ship-days. This marks a slight 12 percent drop from 2024 and a 32 percent decline from a record high in 2023, which saw operations totaling 344 and 444 ship-days, respectively. It is worth noting that this measurement does not necessarily capture all PLA activities in the waters east of China.

Another way to measure the duration of PLAN activities around Japan is to calculatetheir presence by summing up the days in which Chinese ships were conducting a voyage but not directly reported on. For instance, if JMOD reports on a vessel sailing past Japan on a given day and later reports on the same vessel as it returns to China, the total estimated voyage duration includes those days between reports. When measured in this way, China's naval activities in 2025 appear more persistent than in recent years.⁶ In 2025, Chinese military vessels operated at least 999 total estimated ship-days in the East China Sea, the West Philippine Sea, the Sea of Japan, and the Pacific Ocean. This is a marginal decline from 2024, which saw China's naval activities for at least 1070 total estimated ship-days in these waters based on available JMOD data, but is still an increase compared to 2023 and 2022.

One explanation for the growing differences between the known and interpolated ship-days in the past two years is likely that the PLAN is operating beyond Japan and the First Island Chain. This is explored more in the next section.

China has also increased its activities around the Senkaku/Diaoyu Islands, which are a long-standing source of tensions in China-Japan relations. Following major diplomatic disputes in the 2010s, China intensified coast guard operations near the islands, and it has sustained these.

In 2025, a record-high 1,380 CCG and other Chinese state-owned vessels were reported operating within the contiguous zone of the islands. They also sustained their maximum presence around the islands in terms of number of days: they operated within the islands' contiguous zone for 357 days in 2025, compared to 355 days in 2024 and 352 days in 2023. Notably, since mid-2024, China has regularly deployed four CCG vessels together, all armed with deck-mounted autocannons. Previously, China deployed one armed CCG vessel at a time.

While more vessels entered the islands' contiguous zones, fewer Chinese vessels came closer to Japan's claimed territorial waters. Only 89 Chinese vessels entered the islands' territorial seas in 2025, compared to 115 instances in 2024 and 129 instances in 2023.

Of note, in May 2025, a CCG helicopter entered Japan's territorial airspace around the Senkaku/Diaoyu Islands for the first time. The CCG launched the helicopter from a CCG vessel as a small Japanese civilian aircraft flew near the islands, prompting Japan to scramble fighter jets in response. This Chinese operation represents the fourth time since 1945 that Chinese aircraft have entered Japanese airspace. The prior times near the Senkaku Islands involved Chinese fixed-wing aircraft and drones, making the helicopter intrusion a first.

Beyond the First Island Chain

The PLA is steadily building up a "blue wate r" navy capable of operating farther from China's shores. In 2025, the PLAN conducted several unprecedented activities outside of the First Island Chain-the series of archipelagos spanning Japan, Taiwan, portions of the Philippines, and Indonesia that separates the near seas of East and Southeast Asia from the broader Pacific Ocean.

In February 2025, the PLA conducted unprecedented operations around Australia and New Zealand. A three-ship naval task group consisting of an advanced Type 055 cruiser, a frigate, and a replenishment vessel sailed into the Tasman Sea between Australia and New Zealand. The task group conducted live-fire exercises in the area, with little advance warning, forcing dozens of commercial flights to divert. After the drills, the Chinese ships proceeded to circumnavigate Australia before returning to the South China Sea. Australia and New Zealand closely monitored the ships, and their officials voiced complaints about the short-notice alerts and provocative nature of China's activities.

Another notable case occurred in late 2025 when the Australian governmentbegan trackin g a Chinese naval task group-consisting of a large Type 075 amphibious assault ship, a Type 055 cruiser, a frigate, and a replenishment vessel-traveling southeast in the Western Pacific in December. The vessels were later spotted 500 nautical miles north of Palau on December 2. There was an Australian fear at that time that the task group would again circumnavigate Australia. There was also concern about the advanced military capabilities on board the ships, including cruise and ballistic missiles that could range over 1000 kilometers.

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China's aircraft carriers also took several new moves throughout 2025. In May, the Liaoning and its strike group conducted one of its farthest-ever sails away from the Chinese mainland. It reached southwest of Japan's Minamitorishima Island, marking the first time a Chinese aircraft carrier sailed outside the Second Island Chain.

Shortly after that, in June, China's second aircraft carrier, Shandong, along with its strike group escorts,conducted operations in the Western Pacific at the same time that the Liaoning was sailing in the Pacific. This marks the first time two Chinese carrier groups have operated at the same time outside of the First Island Chain and was the longest duration to date of any single Chinese carrier operations outside the First Island Chain.

These developments represent a notable uptick in PLAN carrier activity in recent years. Chinese state media reported that the Liaoning aircraft carrier alone sailed 30,000 nautical miles in 2024 and conducted more sorties in 2024 and 2025 than in the previous four years combined.

In 2025, according to data from JMOD, both Liaoning and Shandong carriers were spotted outside the First Island Chain for 58 days combined, up from 32 total days in 2024, and the highest to date. Japan also reported an estimated 1,680 sorties of fighter jets and helicopters taking off from those aircraft carriers in 2025, compared to 1,240 sorties in 2024 (based on available reports).

Such activities to routinize far-seas combat training are poised to increase in the coming years. China commissioned its third aircraft carrier, Fujian, in November 2025, and the new vessel is far more advanced than its two predecessors. The PLAN is slated to grow its fleet of carriers in the coming years, which will enable China to further expand its military presence farther afield. The 2025 annual report on China's military power, published by the U.S. Department of Defense, assesses that China aims to build six additional carriers between now and 2035 to possess a total of nine carriers.

Notably, China's paramilitary vessels have also been more active in the far seas. In October 2025, CCG ships conducted law enforcement patrols in the Northern Pacific, passing through waters both north and south of Japan's main islands. This follows unprecedented activities in October 2024 in which the CCG conducted joint law enforcement patrols with Russian Border Guard vessels, traversing through the Sea of Japan to the Northern Pacific and reaching as far as the Bering Sea.

China-Russia Joint Military Exercises

Another key area to watch is military cooperation between China and Russia. The two countries have significantly increased their security cooperation in recent years, especially since Russia's 2022 invasion of Ukraine. They have several different mechanisms for military cooperation, including joint exercises, military diplomatic engagements, naval port calls, arms sales (from Russia to China), and others. Of these, military exercises are the most visible and easily trackable, and they offer a useful metric for gauging their military cooperation.

Despite the trend of closer cooperation, there was a marked drop in joint military exercises between the two countries in 2025. That year, China and Russia participated in six joint military exercises and patrols. These included four naval exercises and patrols, a joint aerial patrol, and a ground exercise. This marks the lowest annual total since 2020 and is a significant decrease from 2024, when the two countries held an unprecedented 14 exercises.

Several factors could have influenced this trend. 2024 was a significant year for China and Russia, in which they celebrated the 75th anniversary of the establishment of their diplomatic relations. This flurry of activity may have influenced the unusually high number of exercises in 2024. It is also possible that Russia became more focused on the Ukraine War and wanted to avoid committing as much time and resources to conducting exercises with China.

Despite the lower count in joint activities, several of the 2025 exercises were noteworthy. In August, the two countries conducted their first joint submarine patrol in the East China Sea and Sea of Japan, demonstrating that they are breaking new ground in terms of the types of exercises they conduct.

In December, they also conducted a joint aerial patrol, flying multiple aircraft from the Sea of Japan and through the airspace between Japan's Okinawa Island and Miyako Island. The bombers did a loop that involved flying in the direction of Tokyo before turning back around. The aerial patrol followed Japanese Prime Minister Sanae Takaichi's comment that Japan could respond to a Chinese military action against Taiwan. Japanese Defense Minister Shinjiro Koizumi said the patrol was "clearly intended as a show of force against our nation, which is a serious concern for our national security.