CBERS-1(China-Brazil Earth Resources Satellite No.1)is the first earth resources satellite of China.Its successful emission and running overcome the long-term shortage of depending on foreign satellite data.This paper briefly introduces the types of sensor of the CBERS-1.Then, based on the image of Nanjing area on 1999.11.29, the water system information, especially lake information is extracted and analyzed according to the characteristics of this area. Furthermore, the environment problems of this area facing with are fully and accurately analyzed.