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As we all know, China is one of the famous country for swine. with the development of pig breeding industry, it is important to improve feed-discharging uniformity and sufficient flow in unit time of feeders. A new type of feeder for nursery was designed based on characteristics of mass flow. The principal factors which affected the discharging performance of the feeder were determined through comprehensive analysis. In order to optimize the structural and operating parameters of the designed nursery pig feeder, virtual orthogonal test was carried out by discrete element method software with rotational speed, discharge opening diameter, angle of conical wall of the hopper and filling coefficient as experimental factors and coefficient of variation and flow as evaluation indexes. Based on experimental data, a mathematical model was built by using the Design-Expert 8.0.10 software, and the optimum parameters were obtained. The simulation experiment results showed when rotational speed was 45r/min, discharge opening diameter was 110mm, angle of conical wall of the hopper was 65°, and filling coefficient was 65%, coefficient of variation was 3.96% and flow was 165.93g/s. Then the feeder was designed according to above optimized parameters, and the experiment was done. The results showed that the flow pattern of pelleted feed was mass flow;the relative error of coefficient of variation and the flow was 4.14% and 3.92%, respectively. The results were basically consistent with the simulation optimization, and the designed feeder can meet the feeding needs of nursery pig, which can ensure the quality and efficiency of the operation and provide support for the research and development of pig feeders.