It is imperative to develop new degradable plastic film to prevent and reduce the pollution of farmland residual caused by traditional mulching films. In order to further validate and screen suitable mulch films for spring maize planting in Hetao Irrigation District of Inner Mongolia, four treatments including conventional film, biodegradable film, liquid film and non-film were designed to compare their effects on soil water and heat conditions, yields and water use efficiencies of spring maize. The results showed that no significant difference occurred in soil temperatures between biodegradable and conventional films in early growth stage of spring maize, but 5–15 cm soil temperatures under the two films were significantly higher than those under liquid film and non-film, indicating a good effect of warming and thermal insulation. The insulation effect was reduced due to the damage of biodegradable film in middle and late growth stages of spring maize, but it still kept cooling effect which reduced the harm of high temperature on spring maize. In the whole growth period of spring maize, there was no significant difference in soil moistures between biodegradable and conventional films, but 0–40 cm soil moistures under the two films were significantly higher than those under liquid film and non-film, providing good water conditions for the growth and development of spring maize. Biodegradable and conventional films significantly improved the yields and water use efficiencies of spring maize with no significant difference, but significantly higher than those under liquid film and non-film. In general, it is more appropriate to replace conventional film by biodegradable film in spring maize planting in Hetao irrigation area.