Aiming at the problems of insufficient seed-filling time, poor seed-filling effect and unsatisfactory sowing uniformity of pneumatic precision seed meters during high-speed operation, a pneumatic high-speed precision seed-metering device for maize with double seed metering disks and a staggered hole layout was designed. The basic structure and working process of the seed-metering device were elaborated, a theoretical analysis was conducted on the force acting on seeds during the seed-filling process and the air chamber pressure, and the key structural parameters of the seed-metering disks were determined. Through DEM-CFD coupled simulation, the working performance of the seed-metering device under different vacuum levels was explored, and the influence of seed-disturbing bosses on the seed-filling performance parameters of the seed-metering disks was compared and analyzed. The results showed that the designed seed-disturbing bosses could effectively improve the seed-filling performance. Taking the qualified index, miss-seeding index and multiple-seeding index as evaluation indicators, single-factor and two-factor combination experiments of operating speed and air chamber pressure were carried out. The results indicated that at an operating speed of 12.14 km/h and an air chamber pressure of - 5.15 kPa, the seed metering qualified index reached 95.8%, while both the multiple-seeding index and miss-seeding index were 2.1%, which met the requirements of high-speed precision maize sowing. The research can provide ideas for the development of new high-speed precision maize sowing equipment.