The Chinese People's Liberation Army Daily on Friday carried a photo on its front page of the Changcheng 200 submarine test-firing a missile.
The disclosure of the exercise follows the dramatic test flight earlier this month of a new stealth fighter jet that coincided with the visit of U.S. Defense Secretary Robert Gates.
The news was also reported by the official Xinhua news agency, the web edition of the People's Daily, and the Science and Technology Daily the following day. They did not specify when and where the test took place.
The Changcheng 200, commissioned in 1966, is a large G-class conventional submarine, 98 m long and 8.6 m wide. It is powered by diesel engines and electric motors. The sub first test-launched a missile in 1982, but this was the first time a firing exercise has ever been made public.