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To reduce operating resistance and improve the stability of deeploosening,，a selfexciting vibration deeploosening and subsoiling machine with controllable cutting angle was designed. The range of the cutting angle was controlled in 19°~25°. To optimize parameters of elastic component and validate the effect of drag reduction，the experiment in the soil bin was carried out, furthermore, the field experiment of operation quality and performance of the machine was conducted. The experiment in soil bin showed that the parameter of elastic significantly affected the resistance reduction, when the stiffness of the elastic was 194 N/mm, the traction resistance can be reduced about 29.8%. Also the effect of elastic component parameters on the drag reduction was significant, and under the condition of selfexciting vibration, with controllable penetration angle, the traction resistance was decreased by 8.9% than that with uncontrollable penetration angle. The results of the field experiments showed that the qualified rate of subsoiling depth was 100%, stability coefficient reached 95.49%, the average of soil fluffy and soil disturbance coefficient were 19.34% and 56.62% respectively, the land surface was flat after subsoiling, and the average of the soil crushing rate was 76.4%. Moreover, the trafficability in the period of the test was good, and the machine met the subsoiling technical requirements in doublecropping area in northwest China.