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Based on the problem of high seed damaging, a precision metering was proposed based on the pelleted corn seeds.The two times orthogonal rotational regressive tests were designed in the experiments. The rotary speed, diameter of the cell, cone angle of the metering seeding plate were defined as input parameters and seed damaging index was defined as output parameters. The regression mathematics models between output parameters and input parameters were established and then parameters were optimized through Design-Expert 7.1. The optimal combination was that the rotary speed of 13.2 r/min, diameter of the cell of 16 mm, cone angle of the metering seeding plate of 26.5°, at that time the seed damaging index of 0.65%. Confirmatory tests showed that the inaccuracy was little.