Abstract:A location experiment with different plastic film mulching was conducted in Dongyang Town of Shanxi Province in 2015 and 2016 in order to improve water use efficiency of dry farmland in north China and to explore the application prospect of degradable plastic film. 5 treatments of film mulching were designed:1, common plastic film mulching; 2, water-permeable plastic film mulching; 3, biodegradable plastic film mulching; 4, light degradation film mulching; and 5, no film mulching. The results showed that soil temperatures of film mulching were 3.1–5.9℃ higher than that of CK in the early growth stage. Water use efficiencies of 2, 4, 3 and 1 treatments were 11.0, 5.9, 12.8 and 5.4 kg/(mm·hm2) higher than that of CK. Yield increase rates of 2, 4, 3 and 1 treatments were 20.3%, 0.1%, 15.4% and 8.8% higher than that of CK in 2015, respectively; and were 44.8%, 36.1%, 53.6% and 31.6% higher than that of CK in 2016, respectively. The performance was in an order of biodegradable film > water-permeable film > general film > light degradation film. Yield increasing effect was consistent with water use efficiency attributed to the remarkable effects of film mulching on soil moisture and temperature. The biodegradable plastic film can significantly improve water use efficiency and maize yield, thus and can replace common mulch film in corn production in dry land in the future, which is also helpful in alleviating residual film pollution in farmland.