Chen, seeking to shake off Beijing's claim of sovereignty over self-ruled Taiwan, said last month that it was time to consider scrapping the island's National Unification Council and its guidelines on unification with the mainland.
"This demonstrates once again that he is a troublemaker and saboteur of cross-Strait relations and peace and stability in Asia," Li Weiyi, spokesman for the policy-making Taiwan Affairs Office, told a news conference in Beijing on Wednesday.
He did not mention Chen by name.
The Taiwan Strait, separating the island and the mainland, is considered one of Asia's hottest flashpoints.
Li did not say how China would respond if Chen scrapped the guidelines and council, which was set up in 1990 and was once the island's top policy-making body on the issue of unification.
"This demonstrates once again that he is a troublemaker and saboteur of cross-Strait relations and peace and stability in Asia"
spokesman for China's Taiwan Affairs Office
The council has been dormant since Chen took office in 2000 and ended five decades of Nationalist Party rule.
Beijing has vowed to attack Taiwan if the island formally declares statehood. The two sides split at the end of the Chinese civil war in 1949 when the defeated Nationalists fled into exile on the island.
Taiwan responded swiftly to Li's comments, calling China a troublemaker for its military build-up.
"China's increased military deployment against Taiwan in recent years makes it the troublemaker who unilaterally changes the status quo", Joseph Wu, chairman of Taiwan's Mainland Affairs Council, told reporters on Wednesday.
'Threat to peace'
"Taiwan people and the international community must recognise China is the biggest threat to peace and stability in the Asia-Pacific region".
If Chen dissolved the council and the guidelines, he would break a promise he made in his 2000 inauguration speech.
He had also vowed then not to declare Taiwan formally independent.
Li, the spokesman, said China was still committed to peaceful unification with Taiwan despite provocation.
Moving even before Beijing commented on Chen's statement, the United States restated its support for the "one China" policy that has been the bedrock of Sino-US ties for about
three decades and urged the two sides to avoid misunderstandings.
Washington, which switched diplomatic recognition from Taipei to Beijing in 1979, but remains the island's main arms supplier, reiterated its opposition to moves that could upset delicate ties between China and Taiwan.
Despite simmering bilateral tensions between China and Taiwan, trade, investment and tourism have blossomed with Taiwan investors pouring up to $100 billion into China since
detente began in the late 1980s.