Abstract: Seed metering device is core working component that affects performance of whole seeder.Precision seeding has been widely used in rape seed planting in recent years.According to sowing principle，it could be generally divided into pneumatic seed metering device and mechanical seed metering device.By comparing research status of pneumatic direct seed metering device both in China and other countries，development trend of direct seeding technology and seeding device of mechanization of rice and rape seed was analyzed.Pneumatic direct seed metering device for rice and rape has a broad development prospect.