Abstract: In order to improve the structure parameters of the subsoiler, force analysis to the column subsoiler was carried out and its force mathematical model was established. By changing its parameters, the force status was studied and the influencing degree to the effective resistance of the parameters was found out. At last the design parameters of the subsoiler were optimized based on the above analysis. In order to ensure the accuracy of the mathematical model and the reliability of the simulated results, real field experiments were also carried out to confirm the established force mathematical model. The results proved that the main parameters which affect the effective resistance were working depth, earth-shoveling angle of the subsoiler, working width of the spade handle and the foreward moving speed, and the mathematical model could reflect the subsoiler's real force conditions.