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In order to solve the problems of poor uniformity of depth for wheat cover by soil in the contact seeding form of wheat seeder in China North plain, planting effects were easily affected by some parts of planter, a non-contact mechanical shooting seed-metering device for wheat was developed. Moreover, planting process and structure of planter were also simplified. The key components of the planter was designed, moreover, overall structure and working principle of planter were explained. The shooting performance was influenced by seed distributor and seeding control cage. The process of carrying and accelerating process of planter were analyzed. The rotation speed of seed-metering device, the forward speed, and the shooting height were selected as test factors through theoretical analysis, and the stability of the shooting depth, shooting velocity, average shooting depth and the coefficient of variation of the seed amount were selected as indicators for simulation test and bench test. Moreover, a verification test was conducted in Conservation Tillage Research Center of China Agricultural University, in 2019. The primary and secondary order of influencing factors for each test index were obtained. For the stability of the shooting depth, the significance order was rotation speed of seed-metering device, forward speed, and the shooting height;for the coefficient of variation of the seed amount, the order was forward speed, rotation speed of seed-metering device and shooting height, respectively;for the shooting velocity, the order was forward speed, rotation speed of seed-metering device and shooting height;and for the average shooting depth, the order was forward speed, shooting height and forward speed, rotation speed of seed-metering device and shooting height. In specific, shooting height was a non-significance factor for shooting velocity. The test results showed that when forward speed, rotation speed and shooting height were 1.0m/s, 1100r/min and 100mm, respectively, the stability of the shooting depth, seeding amount variation coefficient, shooting velocity of wheat seed and average shooting depth was 8.3%, 13.9%, 35.2m/s and 34mm, respectively. The experiment verified that the designed mechanical shooting seed-metering device could meet the agronomic requirements of wheat sowing in China North plain. This research provided a method for the design of wheat planter.