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Aiming at the maize sowing synchronous hole fertilization process exists in the seed-fertilizer application position and the amount of fertilizer application is not accurate, poor hole formation of fertilizer by hole application devices and other difficult problems, a kind of pneumatic assisted hole fertilization targeting seed position device was designed. Based on the detected seed drop signal, the pneumatic assisted intermittent fertilizer discharge device converted the continuous fertilizer discharged from the outer chute wheel fertilizer discharger into intermittent fertilizer mass and applied it at a certain position from the seed. The structural composition and working principle of the device were described, the key structural dimensions of which were theoretically analyzed, and the role of airflow on the baffle was analyzed to verify the theoretical feasibility of the device. Based on STM32 microcontroller, a pneumatic assisted hole fertilization targeting seed position control system was developed. Based on the working mode of pneumatic assisted hole fertilization targeting seed position, a hole fertilization targeting seed position control model applicable to high frequency intermittent fertilizer application scenario was constructed, and the hardware circuit and control program were designed. In order to study the performance of hole formation and fertilizer discharge stability of pneumatic assisted intermittent fertilizer discharge device, a discrete element simulation test was conducted based on EDEM. When the forward speed was 3~7km/h, the average length of fertilizer application was 69.8~169.1mm, the coefficient of variation of fertilizer application length was 3.9%~11.9%, and the error of fertilizer discharge ranged was 1.7%~5.5%. By observing the movement state of fertilizer inside the pneumatic assisted intermittent fertilizer discharge device during the simulation process, it was determined that the fertilizer discharge effect was the best when the baffle opening duration was 100ms. Bench test was carried out, the average length of fertilizer applied in individual holes was 75~187mm, the coefficient of variation of fertilizer length was 5.3%~12.4%, the error of fertilizer discharge was 5.6%~12.8%, and the error of hole spacing was 2.5%~6.5%. When targeting seed position hole application was carried out, the average seed-fertilizer longitudinal spacing was 14~113mm. The field experiment results showed that the average fertilization length was 93~189mm and the average seed-fertilizer longitudinal spacing was 34~119mm when the fertilizer amount was 5g/hole. Seed-fertilizer synchronization was good, meeting the maize sowing synchronous hole fertilization operation requirements. The test results were basically consistent with the simulation experiment and the bench test, which verified the reliability of the simulation experiment and the bench test.