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The layered fertilization technology could apply the fertilizer required for the entire growth of corn into the soil in specific ratio, which can not only improve the utilization rate of fertilizer, but also reduce operating procedures, improve operating efficiency, save input and increase efficiency. Aiming at the problems of non-obviously effect of fertilizer layering and difficult-controlling for amount of fertilizer in each layer, which because of the large ditch width and poor soil returning effect, a spatial layered fertilization device with adjustable fertilizer amount in each layer was designed. A semi-enclosed seed distribution was formed in the soil by using this kind of device. The basic structural parameters of the spatial layered fertilization device and the main factors that affected the movement of fertilizer particles in the layered fertilization device was obtained through theoretical analysis and design calculations. The discrete element method was used to simulate the working process of the layered fertilization device. The front-end width, rear-end width and installation angle of fertilization adjustment piece was selected as test factors, and the amount of fertilizer discharged of the upper and middle fertilizer outlets was taken as the experiment indicators for a quadratic-regression orthogonal combination simulation test. A regression model of experiment index was established and influencing factors were obtained. The simulation results showed that the fertilizer application ratio of the upper, middle and lower three-layer fertilizer outlets was the best fertilization ratio as 3∶3∶4, while the front-end width of the fertilization adjustment piece, rear-end width and installation angle was 3.61mm, 21.52mm and 43.23°, respectively. In order to verify the results of the simulation analysis, the prototype performance test of the spatial layered fertilization device was carried out at different operating speeds and fertilization amounts. The test results showed that the spatial layered fertilization device could meet the target fertilization ratio of each layer. The coefficient of variation of fertilizer amount of each layer at different operating speeds and fertilization amounts, depth error of each layer and the horizontal distance error of each layer was within 4.3%, 10mm and 6mm, respectively. The field experiment also showed a stable working performance by using spatial layered fertilization device.