Aiming at the problem that the precision and performance of maize mechanical seed-metering device was decreased and unstable when it was at high-speed sowing of the seeder. The technical idea of adjusting and controlling maize seed filling posture by using posture adjustment teeth and unit hole was put forward. A precision metering device with posture control and driving was designed. It adopted the structural layout of double sided seed discs opposed and single row seeding, so as to reduce the rotation speed and improve the uniformity of seed-metering. The structural parameters of the key components were designed. The principle of seed posture adjustment was analyzed. Through single factor test and combination test, the optimal parameters of the seed-metering device was obtained. Subsequently, the seed-metering performance comparison test were carried out. The results showed that when the type of the posture adjustment teeth was linear, the effect of improving the qualified index was the best, which can be increased by 29.1 percentage points compared with that of no posture adjustment teeth. When the rotation speed was 16.7r/min, the inclination angle of the hole outer wall was 46.9°and the fillet radius of the hole was 4.5mm, the qualified index, missed index and multiple index were 91.6%, 2.8% and 5.6%, respectively. Within the range of operating speed of 8~14km/h, the qualified index was over 90%, the miss index was below 3%, the multiples index was below 8%, the damage index was below 0.5%, and the variation coefficient of grain spacing uniformity was below 19%. Moreover, the seed-metering effect was better than that of no posture control seed-metering device and scoop type seed-metering device, which met the technical requirements of maize precision sowing.