In eutrophic lakes large amount of algae detritus fall down to the lake bottoms every year. Dissolved oxygen in water would be consumed rapidly by labile compositions during degradation and transformation of the organic detritus, which can easily cause water hypoxia, affecting the health of lake ecosystem. Throughout the 4 seasons of 2014, 12 sampling sites for collected from surface sediments in Lake Chaohu were chosen to study the biodegradable organic components. In order to study characteristics of the labile components within the detritus and the distribution in the lake, source of organic matter, TOC, PRT, CHO, LPD and BPC contents in the samples were analyzed. Results have shown that the content of organic matter of surface sediments in Lake Chaohu is high, the average content reached 1.24%. BPC content accounts for 30.99% to 60.48% of TOC. The biodegradable organic components were relatively high, which accumulated obviously in northwestern Chaohu in winter and summer. The organic matter and biodegradable parts of surface sediments mainly adsorbed on the particle size of 48μm, so that the particles ranged from 48μm should be concerned when we use engineering measures to deal with excess organic matter in surface sediments.