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77.3%。Based on the results of the soil-bin test, the lunar soil traction characteristics were studied by DEM software PFC2D. The linear contact-stiffness model was used as DEM contact model for describing lunar soil and biax-test was used to adjust the micro parameters of particles. The results show that parameters of simulated lunar soil in this simulation are close to those of the lunar soil after adjusting the micro parameters. The paper researched the influence of the friction coefficient, porosity, rmax/rmin and gravity of the lunar soil to the traction ability of lunar rover. The results of the simulation test show that the draw bar pull (DP) increased with the increase of friction coefficient, the DP reduced with the increase of porosity, and the DP increased with the increase of rmax/rmin when the value of rmax/rmin is less than 5. The DP is increased with the increase of gravity and the DP is 77.3% of the primary value when the driving wheel passes the lunar soil with 1/6 of the gravity.