Abstract: The effects of water pollution accidents and water environmental pollution on fishery, drinking water source, agricultural and animal husbandary production and industrial production are discussed. The economic loss caused by water pollution is analyzed. It has been indicated that the sluggish and undirectional flow in waterway network area and the alternative water flowing of tidal rivers are the environmental hydraulic causes of water pollution in Jiangsu province. In addition, huge amount of wastewater carried in by entering rivers is also a significant cause of regional water pollution harmfulness.