Abstract: In this paper, an inside-filling seed metering device and the wheat seed were researched by using the discrete element method. The two-dimensional discrete element method analytical model of a seed metering device was established based on its CAD model, and the two-dimensional particle model of a wheat seed was built using the method of combination of different circular arcs. The behaviors of wheat seeds and the performance of the seed metering device were simulated and analyzed using self-developed two-dimensional discrete element method software. By comparing the simulation results with the experimental results, good agreements were obtained. The results showed the feasibility of using discrete element method to analyze the performance of an inside-filling seed metering device, which can be a new method for the research and optimal design of inside-filling seed metering device.