The mechanics behavior between soil and wheel has important influence on the traction performance of the lunar rover. For analyzing the interaction between soil and wheel, the mechanical model is established and the experiment devices adopting gas bearing and tracking mechanism are set up in this paper. The relation of wheel structure, soil parameters, load, slip rate, traction force of the wheel is analyzed. Some experiments are done to test the mechanical property and the effect of slip angle, slip rate and soil parameters on the traction performance of the rover. The results prove the validity of the theoretical model.