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A clamping maize precision seed metering device was designed based on the fitting of different structures of seed-clamping piece in each region and seed-pressing annulus to control the position and movement of seed to get a simple structure, improve the performance of maize seed metering device and meet the requirement of precision planting. The overall structure and working principle of the seed metering device were illustrated and analyzed by the size of maize seeds. The design of structural parameters of key components was conducted, such as seed-clamping piece and seed-pressing annulus. The rule of seed collection mechanics was got by analysis of seed collection process. In order to test the performance of clamping maize seed metering device, the experiment was employed through the method of single factor with Tiannongjiu (big size), Hongqi 688 (middle size) and Huangjinnuo (little size), three kinds of maize seeds. In test, working speed was taken as main influencing factor, the seed qualified index, and multiple index and missing index were taken as response index. The experiment indicated that the clamping maize precision seed metering device fit in the maize seed with big size better and the qualified index was 90.1%, the multiple index was 9.1% and the missing index was 0.8% with Tiannongjiu maize seed at working speed of 11km/h, which could meet the requirement of precision planting. The results can provide guidance and direction for the design and development of high-speed precision mechanical seed-metering device.