Abstract: Jiangnan river web located in Cangnan County，Zhejiang Provice is well developed in industrial and agricultural production, and is densely populated, The river pollution is more and more severe, The water environment safety of the river has been the chief question for industrial development and the people. Based on environmental monitoring data in 13 control sections from 1996 to 2001 on the surface water quality of the river in Cangnan County, the status quo and diversification trend of river pollution was analyzed and assessed.The major point sources and nonpoint sources were identified. Water quality of the major monitoring sections in Heyang branch is between ordersⅡand Ⅲ order, which can basically provide drinking water. Water quality in Jiangnan river web,Xiaojiangtang River and Gansongxi River were all order V, while Jiangnan river web pollution was deteriorated year by year. Water environment protection measures and pollution control planning was proposed based on water environment features and the existing issues.

Key words: Cangnan County, water environment safety, surface water quality, protection measures