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Soil tillage is an important operation to create a better soil condition for crop growing. However, larger draught forces exist in the tillage operation so that it is urgent to need some methods to solve these problems. Mole rat has the outstanding digging performance, and its multi-claw combination would inspire the development of new efficient tillage implements. The mathematical model of the multi-claw combination was established, and bionic soil-cutting blades were designed for investigating the effects of the bionic structural elements (m and n), soil moisture content and rake angle on the draught force. By the quadratic regression orthogonal test, it was found that the soil moisture content and rake angle had more significant effects on the draught force. Optimal combination with the least draught force was m=5 and n=1.75. Through the comparison test of the draught force between conventional and bionic soil-cutting blades at the rake angle of 10° to 90° and the soil moisture content of 10% to 30%, the bionic structural elements had no significant effects on the critical rake angle of blades, but soil moisture content had a significant effect on that. Particularly, the bionic blade showed the best cutting performance. When the soil moisture content was 10%, 20% and 30%, the draught force of the bionic blade was decreased by 11.48% to 39.16%, 17.81% to 28.00% and 11.19% to 33.26%, respectively. Moreover, the bionic blade had better soil cutting performance at the soil moisture content of 10%~20%.