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In order to reduce the rice stubble of minimum tillage and no tillage resistance in the process, improve the quality of work, and provide basis for the design of stubble breaking ditching device, the shear experiments on the universal material testing machine was tested on rice stubble and soil complex. Soil moisture content, soil bulk density, complex stubble soil composite equivalent diameter, cutting position, cutting speed, cutting edge angle and blade shape were tested by single factor test. Based on single factor experiment, the orthogonal experiment was carried out on three factors, including soil moisture content, shear rate and cutting edge angle. The results of single factor test showed that the relationship of ultimate shear force and water complex rate was two-order polynomial function, a power function relationship with soil bulk density, a two order polynomial function relationship with stubble and soil complex diameter, logarithmic relationship with shear velocity. The ultimate shear stress was decreased with the increase of shear distance from stubble, and it was also decreased with the decrease of cutting edge angle;among the four shapes of cutter blade, the ultimate shear stress of concave arc cutting blade was the least. The results of orthogonal test showed that the ultimate shear stress was the minimum when the cutting speed was 450mm/min, the moisture content was 25% and the cutting edge angle was 15°.