From the point of environmental vulnerability, the formation and developmnet of Taihu Lake environmental vulnerability are analyzed. It is found that Taihu Lake is a typical ecotone in China, and the tendency of vulnerability will possibly be reinforced in the future. It is necessary to break away from the ideas such as “the paradise in the world” and “the land of rice and fish”. Based on the character of Taihu Lake environment, the controlling countermeasures of vulnerability are put forward.