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As one of the key technologies of conservation tillage, subsoiling has been widely promoted in northern China, while the large traction resistance and high energy consumption of subsoiling is the main problem of subsoiling. The structural parameters of subsoiler, which included spade shape, penetrating angle and wingspan angle, had significant effects on the soil property of subsoiling trench and the traction resistance of subsoiler. In order to investigate the effect on the soil physical properties (bulk density, soil porosity and cone index) of subsoiling trench in 0~40cm depth, calculate the subsoiling trench crosssectional area (TCA) and the traction resistance of subsoilers, and make optimization for the key structural parameters of subsoiler, the chiselshape subsoiler (CS), arrowheadshape subsoiler (AS) and wingshape subsoiler (WS) were designed and tested under notillage conditions. Orthogonal experiment was conducted in spring maize ridgetillage area which was located in Zhangwu county, Liaoning province in Northeast China. The trench specific resistance (TSR) of the above three subsoilers had also been calculated. The results indicated that penetrating angle α and wingspan angle β had no significant effect on the change of soil physical properties, TCA and TSR, while the change of α had a significant influence on the traction resistance, and it would be the minimum subsioler when α was 21°. The spade shape of subsoilers affected soil physical properties, TCA, traction resistance and TSR significantly. The soil disturbance extent of subsoiling and TCA were increased in accordance with the order of CS, AS and WS. TCA for WS was greater than those for CS and AS by 49.8% and 30.0%, respectively, and TCA for AS was greater than that for CS by 15.3%（P＜0.05）. However, the traction resistance for WS was greater than those for CS and AS by 123.6% and 36.6%, respectively, and the traction resistance for AS was greater than that for CS by 63.7%（P＜0.05）. TSR was significantly affected by the spade shape, and it was increased with the order of CS, AS and WS. TSR for CS was less than those for AS and WS by 42.4% and 50.2%, respectively, and TSR for AS was less than that for WS by 5.4%. The analysis result showed that if it was just to get relatively more soil disturbance, WS would be the best choice when its penetrating angle αwas 21°. While taking subsoiling trench’s soil properties, TCA and traction resistance, especially TSR into consideration, the relatively best subsoiler was chisel shape subsoiler (CS) when its penetrating angle α was 21°.