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In order to shorten the corn seeding period, reduce the waste of corn seeds and insure the sowing quality, the highspeed precise seeding technology has become an important direction of corn seeder development, which mainly includes pneumatic type of corn seeder and mechanical type of corn seeder. So the corn metering device which is the core component of corn seeder attracted many experts and scholars to study. And the results showed that the pneumatic corn metering device existed inaccurate sowing precision and the mechanical corn metering device owns poor adaptability for highspeed operation and different corn seed shapes and so on. According to the above practical problems, a telescopic clip finger type of corn precise metering device was developed which owns two advantages such as simple structure and good seeding performance. Its influenced laws with the main structural parameters to the metering performance were firstly studied, and the main parameters influenced the metering performance were determined by the orthogonal test method which included clamping force, opening distance of clipfinger and the rotating speed of metering plate. And their optimal experimental results were: the clamping force of 0.87N, opening distance of 16mm and the rotating speed of metering plate of 45r/min. And the corresponding performance indexes are as following: the spacing of the qualified rate is 95.4%, the leakage sowing rate is 1.9% and the replanting rate is 2.7%, which could completely meet the requirement of the technical specifications of quality evaluation for drills in China. The research provides a reference for further improving quality and optimizing the parameter for clip finger type of metering device.