Fighter jets launched strikes and warships opened fired to destroy an enemy beachhead, while more than 3,000 soldiers took part in the live-fire drill in the southern county of Pingtung.
During annual military exercises across the island this week, fighter jets have landed on Taiwan`s main highway and air raid drills have shut its major cities.
While it was just a mock exercise, Defence Minister Yen Teh-fa left no doubt where the greatest perceived threat lay.
Taiwan is one of a growing number of flashpoints in the US-China relationship, which include an escalating trade war and China`s muscular military posture in the South China Sea, where the United States also conducts freedom-of-navigation patrols.
Earlier this month, senior US and Taiwanese security officials held a rare meeting, a move that angered Beijing.
China has stepped up pressure on Taiwan, suspecting that its President Tsai Ing-wen is pushing for the island's formal independence - a red line for Beijing.