A kind of axial draft sensor was designed based on magnetostriction theory to improve the measuring accuracy of soil resistance. A mathematical model of sensor’s exciting circuit was established based on ferromagnetics theory, Ampere’s circulation and Ohm’s law for magnetic path. Then the performances of sensor’s output signal along with load were simulated by using Matlab/Simulink. 45-quenching steel and 40Cr-quenching steel were used as sensor’s shell separately. Load experiment showed that the performance of the sensor, of which shell was 45-quenching steel, was better than the other. The better sensor’s linearity determination coefficient of static characteristic curves was 0.9965. The output voltage was 0.55 V when the shearing force was 70 kN. 