Abstract: This paper presents an automatic precision seeding system, it has high automatic level, operation convenience, good adaptation for odd seeds, high productivity, low miss index, low multiple index and other advantages. The system consists of automatic soil filling, seeding, soil covering, watering and tray conveying devices. The controlling unit based on the single-chip microcomputer of MCS-51 series, it receives signals from optical sensors (used to check position of tray and seeding drum) and controls all the devices automatically. The experiment showed: below the productivity of 720 trays per hour, its miss index and multiple index are 1.85%, 2.31% for bean seeds and 3.70%, 4.62% for corn seeds respectively.