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Traditional precision maize planters mostly use land wheel to drive or measure speed, the phenomenon of land wheel slippage and chain hopping is easy to occur under high-speed operation conditions, so it’s difficult to ensure the seeding quality. In allusion to the problems mentioned above, a control system of motor-driving maize precision planter based on GPS speed measurement was proposed. Different from traditional maize precision planters’ control system, in the new control system, STM32 was utilized as the MCU, Android-powered devices were adopted to set seeding parameters, GPS receivers were used to collect the tractor’s working speed, the rotational speed of motor would vary with the tractor’s working speed in real time, and then the sowing axis’ rotational speed would match the tractor’s working speed dynamically. To check up the performance of the new control system, the comparison test was carried out at three plant spacings of 18cm, 22cm and 25cm, and five speeds of 4km/h, 6km/h, 8km/h, 10km/h and 12km/h. The field experiment results demonstrated that distance variation coefficient of the control system based on GPS was less than control system based on encoder under the same experimental conditions, sowing qualified index and distance variation coefficient of the control system based on encoder was more predominantly affected by working speed than control system based on GPS. Under different plant spacing conditions, the average sowing qualified index of the control system based on GPS was 5.39 percentage points lower than that of the control system based on encoder while working speed was 4km/h. Increased working speed to 6~10km/h, the GPS mode was 7.96 percentage points higher than that of encoder mode. When the working speed was risen to 12km/h, the GPS mode was 14.32 percentage points higher than that of encoder mode.