In order to reduce working resistance and power consumption of subsoiler, and improve the applicability to different soil, 1SZ-600 selfexcited vibration subsoiler characterized by adjustable spring pretightening force was designed. The main part of the selfexcited vibrating subsoiler was tension spring, parameters of the spring were determined through subsoiler overall structure and springs location. Working resistance reduction was achieved by selfexcitation vibration unit. The pretightening force of spring was changeable according to soil mechanical properties. Field experiment was conducted in Guan County, Hebei Province. Experimental factors included working depth of 250mm, 300mm and 350mm, operating speed of 2.5km/h, 3.2km/h and 4.0km/h. Results showed that to ensure the premise of deep tillage, selecting appropriate spring preload can effectively reduce the traction resistance. 〖JP2〗The draft resistance was decreased by 19.26%, 15.43% and 22.65% at working depth of 25cm, 30cm and 35cm 〖JP〗with working speed of 2.5km/h, respectively. When the working speed was 4km/h, draft resistance was decreased by 10.3%, 13.9% and 21.4%, respectively. Traction resistance reduction was obvious with higher working speed and it was decreased by 10.30%~22.65% compared with nonvibrating subsoiler at any speeds and working depths. Variance analysis was conducted to ensure the significant influence of test factors. Results showed that working speed, tillage depth and machine structures had significant influence on the traction resistance. The increase rate of the traction resistance of vibration was less than that of non vibration with the increase of tillage depth at different operating speeds due to drag reduction of a selfexcited vibration unit.