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High speed and high precision is the development trend of maize precision planter，under the premise of ensuring the seeding quality of operation reached the national standard,，the working speed of the existing pneumatic seed metering device can reach more than 12km/h,，traditional maize precision planter mostly used 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 and exert the potential of the highspeed operation of the seed meter device. In addition, the maize precision planter only has a single function, and the sowing plant spacing is mostly adjusted by gear set, so it is not possible to achieve stepless adjustment of plant spacing. A maize precision planter monitoring system based on Android and CAN bus was designed, as the system was working, the speed of the planter was collected by GPS receiver, after parsing the speed information from the GPS signal, the master controller would send the driving motor speed adjustment instruction according to the seeding operation parameters, and the command transmission between the master controller and each seeding unit was completed by CAN bus. Human machine interaction through Android smart device can realize the functions of arbitrary expansion of seeding rows, realtime monitoring of planter position, online adjustment of seeding operation parameters, and realtime statistics of working area. In order to test the performance of the system, bench test and field test were carried out respectively. The bench test results showed that the systems humancomputer interaction function was normal, the position, speed and working area of the planter and rotation speed of the meter can be displayed correctly. The relative error of the metering drive motor speed regulation was less than 0.45%. Field comparison test with area measurement of eTrex209x handheld GPS+ Beidou binary receiver showed that the statistical average relative error of the operating area of the system was 0.81%, which was inferior to that of 0.29% of eTrex209x, and the measurement standard deviation was 0.06hm2, which was better than 0.11hm2 of eTrex209x; grounddriven seeding comparison test was carried out at plant spacing of 21cm, and five speeds of 4km/h, 6km/h, 8km/h, 10km/h and 12km/h,， the test results showed that the quality of the two driving modes was decreased with the increase of the working speed, but the qualified index and distance variation coefficient of the system were less affected by the speed than ground wheel drive mode, when the operating speed reached 12km/h, the distance variation coefficient did not exceed 18.92%, and the qualified index was 90.05%, which was better than that of 22.17% and 83.25% of the ground wheel drive mode.