【Objective】 Sand-layered soil is widely distributed in the Hetao Irrigation District of Inner Mongolia, and its water and salt migration processes are more complicated than that in a homogeneous soil. Therefore, this study was designed to investigate the effects of different thresholds of drip irrigation on water and salt re-distribution in a sand-layered soil profile and on crop growth and water use.【Method】A two-year field experiment was conducted in a sand-layered soil field at the Hetao Irrigation District during spring maize growing seasons in 2017 and 2018. For this soil profile, the depth between 60~100 cm was sand-layer. The experiment included 5 irrigation thresholds under mulched drip irrigation, which controlled the threshold values of soil matric potential (SMP) at –10 kPa(S1), –20 kPa(S2), –30 kPa(S3), –40 kPa(S4), and –50 kPa(S5)respectively, for spring maize planting. The soil volumetric water content, water storage, salt distribution and storage in 0~120 cm soil profile, and maize grain yield and water use efficiency were analyzed. 【Result】The presence of sand layer affected the water and salt movement in the soil profile. This resulted in a significant difference in the vertical distribution of water and salt in the soil profile. The soil volumetric water content was relatively lower in the root layer between 0~60 cm depth, but higher in the sand layer between 60~100 cm depth. The soil volumetric water content in the sand layer was always kept around the level of field water capacity during maize’s growing seasons. Due to the water movement in the soil profile, more salt was concentrated in the sand layer. The abrupt transition points of distribution of water and salt in the profile appeared at an upper boundary of the sand layer. These distribution characteristics of water and salt were consistent during different growth periods. Besides, different thresholds of drip irrigation significantly affected the distribution and storage of soil moisture and salinity in different soil layers. At higher soil volumetric water content, the lowest soil EC_1:5(electrical conductivity of 1:5 soil/water extract) were observed in the root layer. Nevertheless, the difference between the soil moisture content and salt content in the sand layer and below was not significant. The grain yields of maize treated with S1, S2, and S3 were significantly higher than those of S4 and S5 (P<0.05), but the difference among the former three was not significant. Also, the water use efficiency (WUE) of maize increased first and then decreased with the decrease in irrigation thresholds, and S3 had the highest WUE. 【Conclusion】Lower irrigation thresholds favored grain yield relative to higher thresholds. Considering the water and salt environment in the root layer and WUE, it is suggested that the threshold of irrigation should be –30 kPa when cropping spring maize in this sand-layered field using mulched drip irrigation.