Abstract: The integrated system described in the paper combines the geographic information system software based on a vector data structure with a simulation model for non-point sources(NPS) pollution management.Territory is disaggregated into a series of irregular vector polygons for spatial modeling units of NPS through many map overlays such as land-use types,soil cover,subwatershed layers,and the case is studied in Suzhou creek,Shanghai.The structure,functions and database of the seamless integrated Suzhou creek NPS pollution management system are designed based on the COMGIS MapX,surfer software platform.At the end,the management system is developed.The integrated system can perform effectively the pollution loading estimation,the pollution index evaluation,the isoline output of unit pollution loading,and total quantity control of NPS pollution.Our integrated system is not only an available test of NPS professional software,but also an available probe of digital watershed environmental management.