[Objective] The investigation and evaluation of agricultural non-point source pollution in small watershed of Zhongxing Reservoir of Chaohu Lake basin, Anhui Province, were conducted to understand the status quo and characteristics of agricultural non-point source pollution in this area and to provide reference for the pollution prevention and control measures.[Methods] Using standard pollution load method, the pollution status in the Chaohu Lake basin, Zhongxing Reservoir small watershed was investigated by questionnaires method and measured whereafter. The non-point pollutions sourced from cultivation, breeding and human living of three villages around the reservoir, were classified and accounted.[Results] ① The pollution and pollutant discharge rate of aquaculture industry was the largest in the three villages around the Xingxing Reservoir project area. The pollutant discharge reached to 109.00 t, the maximum pollution load rate was 57.52%. The pollutant amount from planting industry fertilization was up to 25.52 t, had a load rate of 13.47%. The pollution load of human living was 29.01%, and the total amount of pollutants was 54.97 t. ② For the three evaluation factors of chemical oxygen demand(COD), TN and TP, they had the pollution load rates 74.26%, 21.13%, and 4.61%, respectively.[Conclusion] The discharge of pollutants in aquaculture in small watershed is the main influence factor for drinking water safety in Zhongxing reservoir water source, and it should be focused in agricultural non-point source pollution prevention and control.