Abstract: In view of the lake water environmental monitoring actual demand,we have integrated the water environmental basic data,remote sensing information,hydrological and meteorological information and environment model based on the second survey of lake resources.The professional remote sensing model has been formed by using the ENVI/IDL languages for the national key lake,and the monitoring system has been established.The overall framework of the system structure,process and main functions are introduced in detail.Then taking the Taihu Lake as a research object,the thematic products of water environmental are made.And the results indicate that the system has the platform independency characteristic,man-machine interface is friendly and can effectively gain the spatial and temporal distribution of water quality.