The Qiantang River is a typical river flowing through an agricultural area in China. It was studied in 2006 for its aquatic biota quality by determining 13 organochlorine pesticides (OCPs) in the edible parts of crabs, clams, shrimp, fish, aquatic plants, as well as water and sediments collected from seven sites along its upper reaches all the way downstream. The levels of all insecticides were in the range of 17+/-13 (water plants), 35+/-36 (shrimp), 32+/-14 (crabs), 39+/-21 (clams), 47+/-35 (fish) ng/g wet weight (ww) and in the range of 2936+/-2356 (water plants), 5827+/-6013 (shrimp), 2102+/-966 (crabs), 1859+/-1018 (clams), 3624+/-11331 (fish) ng/g lipid. DDT and its metabolites were the predominant contaminants in most biota. A linear relationship was observed between the log bio-concentration factor (BCF) and log octanol-water partition coefficients (Kow) for fish, clams and shrimp. Composition analyses in various environmental media indicated a recent usage of lindane and dicofol into the river.