In view of the problems faced in the land preparation operation in northeast China, such as more clods, serious soil stubble and thickened plow bottom layer, a driven soil crushing and preparation combination machine mainly applicable to potato fields was designed according to the power conditions of the existing Dongfanghong-75 and 802 tractors. This was a new type of machine designed according to the advanced foreign soil conservation tillage method and developed by combining the soil conditions of the northeast and the requirements of potato field preparation. The overall structure and working principle of the machine were described. By designing the soil crushing roller, the author clarified and analyzed the soil crushing roller motion process, the resistance of the wedge-shaped teeth during the working process of the soil crushing roller and the power required during the operation of the soil crushing roller. Based on EDEM discrete element simulation technology, a component-soil simulation model was established with soil crushing rate as test index, and end deflection angle of crushing straight tooth, length of crushing straight edge and unit speed as test influencing factors for simulation experiments. The field tests were conducted on the basis of simulation. The test results showed that the designed soil crusher had a soil crushing rate of 98.45%, an average tillage depth of 14.5cm, a unit speed of 5.7m/s and a crushing roller power consumption of 19.24kW, which proved to have a good operation effect and met the requirements of potato field preparation.