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For the repression of hilly area in Northeast China, the soil moisture content of different topography is different and the topography varies greatly. To achieve better repression effect, the corresponding load and forward speed need to be matched. In order to find the optimal level combination of rigid crushing wheel operation in hilly areas, velocity variables were firstly added to establish a dynamic repression and soil mechanism model based on quasistatic principle of repressive and soil mechanism model, and seek soil moisture content, load and advancement. The relationship between speed and soil subsidence and working resistance was then obtained based on SPH algorithm to construct a threedimensional simulation model of rigid repression wheel and soil in LS-DYNA software to simulate the dynamic process of interaction between rigid repressing wheel and soil. The numerical simulation method was combined with the central surface composite response test scheme to carry out the simulation test. The mathematical regression model of soil water content, load, forward speed, soil subsidence and working resistance was obtained by simulation test. On this basis, the R language was used. The ant colony algorithm performed multiobjective optimization on the mathematical regression model to obtain the Pareto optimal solution set, and the water contents of（12±0.1）%,（14±0.1）%,（16±0.1）%,（18±0.1）% and （20±0.1）% were selected to find the five optimal solutions. The soil trough test was carried out to verify the optimal solution. The error between the test result and prediction result was less than 12%, which indicated the reliability of test optimization result and also verified the feasibility of simulation. The research result can provide theoretical and data basis for the research of planter and supporting technology in hilly area.