In order to determine the effects of different mulching methods on soil water depletion, water consumption patterns, water use efficiency, yield and yield formation in dryland potato fields, five mulching methods, including whole maize straw strip double row mulching (SSM2), whole maize straw strip single row mulching (SSM1), full mulching of maize straw (SFM), plastic film spring mulching (PMS) and plastic film autumn mulching (PMA), were set up in the semi-arid agricultural region of Longzhong, with the traditional bare land as the control (CK). The results showed that compared with CK, Soil water consumption increased by 13.5 and 14.8 mm for the whole maize straw strip mulching and plastic film mulching. The whole maize straw strip mulching could significantly increase the contribution of precipitation to potato water consumption, the highest contribution was found in SSM2 in different rainfall year types, 95.6% and 94.3% respectively in two years. Compared with CK, all mulching treatments reduced water consumption in the early growth stage (from sowing to tuber initiation), the whole maize straw strip mulching increased water consumption in the later growth stage (from starch accumulation to harvest), and the plastic film mulching increased water consumption in the middle growth stage (from tuber initiation to starch accumulation). The whole maize straw strip mulching and plastic film mulching increased drying tuber yield of potatoes by 27.9% and 24.2%, and water use efficiency increased by 23.1% and 19.3%. In conclusion, it can be seen that the whole maize straw strip mulching could significantly increase the soil water storage consumption during the full growth stage of potato, and improve the water consumption in the early and later growth stages, reduce the inefficient water consumption in dryland potato farms, and significantly improve drying tuber yield and water use efficiency of potato.