Abstract: 【Objective】 Study the effects of different straw returning methods and plastic film mulching on soil water and nutrient contents, yield and water use efficiency of spring maize (Zea mays L.) in arid areas in order to find out the effects of different straw returning methods on fertility and yield, and to seek a green and efficient way of straw utilization in the hope of providing scientific and technological support for high-quality agricultural development in arid areas of Northwest China. 【Methods】 A field experiment was conducted in Huining County, Gansu Province from 2019 to 2020, six treatments were set up, namely straw returning to the field without plastic film (CK), straw comminution returning to the field (SS), straw fermenting returning to the field (FS), straw returning to the field without plastic film mulching (Mk), straw comminution returning to the field + plastic film mulching (MS), and straw fermenting returning to the field + plastic film mulching (MFS), soil water content, water storage and water consumption, soil carbon, nitrogen, phosphorus and potassium, crop water use efficiency, dry matter accumulation and yield were measured. 【Results】 Under the two treatments of plastic film mulching, the water storage and water use efficiency of plough layer increased by 7.33%-16.29% and 10.73%-19.25%, respectively, the water storage and water use efficiency of plough layer increased by 6.39% and 7.38% compared with that of straw comminution. Plastic film mulching could further increase soil water storage and water use efficiency by 10.62%-16.29% and 13.88%-18.87%, respectively, and increase soil nutrient content, the contents of soil organic carbon, total nitrogen, available phosphorus and available potassium increased by 0.70%-8.03%, 1.63%-8.01%, 7.75%-13.86%, 9.19%-40.48% and 4.06%-10.62%, respectively. Compared with straw returning or film mulching, the dry matter quality and yield increased by 3.10%-15.35%, 11.02%-17.08%, 1.84%-12.81%, 8.94%-14.83%, respectively, the average was 12.04% and 10.08%. 【Conclusion】 Straw returning and plastic film mulching can improve soil water supply and fertilizer supply by regulating soil moisture and nutrients, and then promote the synchronous increase of crop dry matter accumulation and yield. The effect of MFS is better than that of MS, which was beneficial to the multiple objectives of drought resistance, fertilizer increase, efficiency increase and high yield of spring maize.