Abstract: iulong River is an important drinking water source for the cities of Longyan, Zhangzhou and Xiamen. At the same time, this basin isalso a coastal one. At present, nonpoint source pollution,especially agricultural nonpoint source pollution in the upstream has been particularly significant, so this study on agricultural nonpoint source pollution in Jiulong River basin has important realistic meaning and theoretic value. AGNPS(agricultural non-point source)? model is a computer model specialized for simulating soil erosion, nutrient drain and predicting agricultural non-point source pollution of a subwatershed. Wuchuan catchment in the upstream of Jiulong River was selected as a study site. The AGNPS model was adopted to simulate agricultural nonpoint source pollution. According to actual data, the AGNPS model was confirmed to be suitable in this basin. The studies show that predicted results coincide with observed results, so the paper suggests that this model is suitable for prediction and assessment of nitrogen and phosphorus losses in red soil hilly areas, southern China.