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Uniform design was used to test the soybean seeding performance of an air-blowing vertical-rotor type precision seed-metering device in laboratory. Based on test results, regression models of seeding performance were constructed by uniform design software UST 1-0. The effects of designing and operating parameters of air-blowing vertical rotor seeder on its performance were investigated. The results suggest that seeding performance is sensitive to air pressure and operating speed in air-blowing condition. The qualified seeding rate is over 85% in 1.4～1.8kPa air pressure and can satisfy the needs to seed soybean at over 8km/h operating speed. Seeding performance of the air-blowing vertical-rotor type precision seed-metering device is insensitive to seed-filling angle and seed-cleaning angle. The optimized results for seed-filling angle and seed-cleaning angle are consistent with the results at atmospheric pressure, which are 46.35° and 55° for seed-filling angle and seed-cleaning angle respectively. There is no remarkable influence of the airblowing direction on seeding performance.