Abstract:Based on the synchronous water quality and quantity monitoring of the rivers surrounding Lake Taihu in Zhejiang Province during hydrological year of 2010-2011, we have made a thorough analysis over the temporal and spatial variations of water quantity, quality and pollutant fluxes of the rivers connected to the Lake Taihu with the jurisdiction of Zhejiang Province. In the whole hydrological year, total inflowing water was 22.890×108 m3, and total outflowing water was 31.576×108 m3, water quality of the rivers was regular and steady, indexes of main pollutants were categorized into National Grade Ⅱ-Ⅲ. The estimation of pollutant fluxes has shown that the CODMn, ammonia nitrogen, total phosphorus and total nitrogen outfluxes were more than influxes. The decline of pollutants influxes is mainly due to the increases of countercurrent flow of rivers flowing into the Lake Taihu.