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Aiming at the problems of low mechanization level of topdressing, high hardness of soil and fertilizer utilization in the period of large bell mouth of corn, on the basis of the agricultural requirements of row spacing and plant spacing of corn in the Huang-Huai-Hai area, a roller type hole fertilization device was designed. In order to meet the requirements of stable and deep application of hole fertilizer applicator, the dynamic model of the fertilizer applicator was established based on Abaqus, and the hole forming performance and hole pressure of hole fertilizer applicator were analyzed，the analysis results were used to design and select the hydraulic system. According to the requirement of stable performance of hole fertilizer applicator, a discrete element model of machine-soil-fertilizer was established by using EDEM, and its soil throwing characteristics and hole application amount were analyzed at three operating speeds. When the operating speed of roller hole fertilization device was 1.5m/s, the effect of fertilizer discharge was the best. The results of experiment showed that the average hole discharge was 9.01g, the deviation of fertilizer output was 11.2%, the coefficient of variation of fertilization uniformity was 4.17%;the qualified rate of fertilization depth was 92%, and the coefficient of variation was 6.75%, which conformed to the design requirements. The research result provided a method for solving the design of corn topdressing machinery.