Abstract: With the purpose of promoting rainfall utilization efficiency and mitigating environmental pollution caused by plastic film utilization in dry farming area, plastic film, biodegradable film and liquid film were used to research the rainfall harvesting planting during corn growth period in the arid highland of northern Wei River basin. The results indicated that, when treated with plastic film and biodegradable film covering, the moisture storage of soil at depth range of 0-60 cm increased during the whole growth period of experimental corn sample, and showed a significant difference (P<0.05) comparing with the liquid film covering treat and no covering treat (CK). The spatial variation of soil moisture showed no difference with different mulching materials; plastic film and biodegradable film covering efficiently improved the soil moisture storage and enhanced the moisture storage stability of soil at depth range of 0-200 cm. When treated with plastic film and biodegradable film covering, the grain yield of corn increased by 19.96% and 19.67% respectively, and the water use efficiency increased by 32.08% and 31.81%, respectively. Therefore, biodegradable film and plastic film has significant effect on soil water conservation and corn yield, and shows no big difference between them, biodegradable film can be used in agricultural production in replace of the plastic film..