Based on the status that the cell parameters of the horizontal plate precision metering device were developed according to designer experiences for a long time, it was difficult to design the reasonable cell parameter, and to select reasonable cell type by seed dimensions. Based on the theory and structure of the horizontal plate precision metering device in this paper, along with distribution characteristic of seed dimensions, static characteristic filling into the cell of the different seed types by analyzing the big circle, the small circle, the big flat and the small flat, a mathematic model of the cell parameters was established, and working characteristic of the cell was attained through experiment in the meter test-bed, and the statistic program developed by the Lab Windows CVI software was applied to calculate different performance indexes. The results confirmed that this is a reasonable model used for the design of cell parameters, and this model should be used to design bases of the cell parameters of the horizontal plate precision metering device and select the cell type according to different seed type.