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A cell wheel metering device and the soybean seed were researched by using the discrete element method. The 3-D discrete element method analytical model of the seed metering device was built on its 3-D CAD model extracted through the method which was based on graphic elements and the surface mesh, and the 3-D particle model of soybean seeds were established on the spherical particle. The metering performance，the trajectories and dropping angles of the soybean seeds were simulated and analyzed by using self-developed 3-D CAE software. It showed that the metering performance,，the dropping angles and trajectories of the seeds were good agree with the experiment results by comparing the analytical results of simulation. This result showed the feasibility of using the discrete element method to analyze the performance of the cell wheel metering device.