In view of the high power consumption of the double axis rotary cultivator, it is difficult to carry out research on drag reduction and consumption reduction only by the method of field trials because of the complex structural parameters and the high manufacturing cost of the equipment. Based on the discrete element method, a biaxial rotary tillage-straw-soil tillage model was constructed, the influence of biaxial configuration parameters on power consumption was studied, and a mathematical prediction model for power consumption through response surface test analysis was established. The optimization results of the model showed that the gyration radius of the front and rear tool shafts was 195mm, the vertical distance of the rear shaft relative to the front shaft was 99.8mm, the horizontal distance of the front and rear shaft gyration circle was 100.6mm, and the minimum power consumption obtained was 9.018kW. In order to verify the accuracy of the power consumption model, under fixed operating parameters, a full-scale simulation test and a field test were carried out. The test results showed that the field test power consumption of the real original scale rotary cultivator and the simulation value of the whole machine were 9.5%, and the range was 5.8%~13.4%. Combined with the response surface analysis, it was showed that the mathematical prediction model of power consumption was more accurate, indicating that the error of rotary cultivator model was small during the scaling process, and the model can accurately reflect the influence of the dual-axis configuration parameters on the power consumption of the double axis rotary tiller in the rice stubble field.