Abstract: A case study was performed of the "pig-biogas-fruit-fish" eco-agriculture model in Xinglin Farm,which is located in Longtang Township,Dingnan County,Jiangxi Province,for systematic study on key techniques and agricultural non-point pollution control effect of the model.The farm planted trees on top of the hills for soil and water conservation,and navel orange trees in terrace fields with grasses growing like a cover on the hillside,kept protective vegetation belts at the foot of the hills,set up pigsties and biogas digestors in the valley and built up multi-leveled fish ponds in the downward,thus forming an integrated "pig-biogas-fruit-fish" eco-agricultural system that features closed material cycle,cascade use of energy and ecological protection.The extension of this model may effectively help the control of agricultural non-point pollution,prevent water quality degradation of the headwaters of Dongjiang River and yield remarkable ecological,economic and social benefits as well.