Democratically governed Taiwan, which China views as its own territory, had been on alert for more war games since Thursday's national day speech by President Lai Ching-te.
Beijing condemned the address after Lai said China had no right to represent Taiwan even as he offered to co-operate with Beijing.
Taiwanese President Lai Ching-te's national day speech on Thursday drew condemnation from China. (AP PHOTO)
The Chinese military in a statement said the "Joint Sword-2024B" drills were taking place in the Taiwan Strait and areas to the north, south and east of Taiwan.
"The drill also serves as a stern warning to the separatist acts of Taiwan independence forces," it said.
"It is a legitimate and necessary operation for safeguarding state sovereignty and national unity."
The command published a map showing nine areas around Taiwan where the drills would take place - two on the island's east coast, three on the west coast, one to the north and three around Taiwan-controlled islands next to the Chinese coast.
Taiwan's defence ministry expressed its strong condemnation of China's "irrational and provocative act", adding it had dispatched its own forces.
Lai's national day speech highlighted the current state of cross-strait relations and the firm will to safeguard peace and stability, and advocated future co-operation in coping with challenges like climate change, the ministry added.
"The Chinese communist's claim of 'picking quarrels and provoking trouble' is a complete departure from the truth," it said.
China held the "Joint Sword-2024A" drills for two days around Taiwan in May shortly after Lai took office, saying they were "punishment" for separatist content in his inauguration speech.
Lai has repeatedly offered talks with China but has been rebuffed. He says only Taiwan's people can decide their future and rejects Beijing's sovereignty claims.