Ten Chinese air force aircraft entered Taiwan's air defence zone on Wednesday accompanying five Chinese warships engaged in "combat readiness" patrols, the island's defence ministry said, the second such incursion this week.
Taiwan, which China claims as its territory, has repeatedly complained of Chinese military activity near it over the past three years, as Beijing steps up pressure to try to force the island to accept its sovereignty.
Taiwan's defence ministry said that starting at around 9 a.m. (0100 GMT), it detected a total of 25 Chinese aircraft engaging in operations out at sea, including J-10 and J-16 fighters, as well as H-6 bombers.
The ADIZ is a broad area Taiwan monitors and patrols to give its forces more time to respond to threats, and Chinese aircraft have not entered territorial Taiwanese air space.
China staged war games around Taiwan in April after President Tsai Ing-wen returned home from a visit to the United States where she met U.S. House Speaker Kevin McCarthy.
Taiwan Vice President William Lai leaves for the United States this week on his way to Paraguay on what is officially only a transit but which has angered China.
Taiwan's democratically elected government rejects China's sovereignty claim and says only the island's people can decide their future.