Abstract: In order to explore the influence of the depth of plough bottom on soil water and salt transport under mulched drip irrigation, the soil column test and simulation method were used to investigate the soil water and salt transport law under different plough bottom depths (no plough bottom, CK; 25 cm depth, PB 25; 30 cm depth, PB 30; 35 cm depth, PB 35; 40 cm depth, PB 40; 45 cm depth, PB 45). The results showed that plough bottom could hinder water movement, reduce water infiltration rate, with a certain water holding capacity. After evaporation, the soil moisture contents of the 10-20 cm soil layer with PB treatments were higher than that of CK treatment. The effect of “salt washing” above 10-20 cm soil layer with CK treatment was better than that of PB treatments. With the increase of plough bottom depth, the phenomenon of surface soil salt returning was gradually aggravated. Under the condition of mulched drip irrigation, the HYDRUS-2D model was used to simulate the law of soil water and salt movement, showing a good effect the verification of measured data. According to the characteristics of water absorption and salt tolerance in the different crops, the moderately deep ploughing should be carried out to break the plough bottom and create a suitable water and salt environment for crop growth. The results could provide a reference for the improvement of saline alkali land and sustainable development of agricultural production in Xinjiang.