Abstract: The organic pollutants in Taihu Lake were determined by gas chromatography. In order to analyze the pollutants with a wide range of boiling points, Supercritical Fluid Extraction and Thermal Desorption were used for the sample preparations. Beside the hydrocarbons, the nitrogen containing compounds were found as the important organic pollutants in Taihu Lake. It can be seen from the distribution of the pollutants that the industrial pollutants from the river adjacent to Taihu Lake is one of the important reasons caused the eutrophication of Taihu Lake.