The invention discloses a water-evaporation-inhibiting environment-friendly cover material used for arid and semi-arid regions and a use method of the water-evaporation-inhibiting environment-friendlycover material used for the arid and semi-arid regions. A main raw material is water-soluble polylactic resin, and a compounded chemical fertilizer is added, so that not only is the water solubilityof the resin improved, but also the purpose of crop fertilization is achieved with water retention achieved at the same time, the powder cover material is dissolved in water, a produced aqueous solution is evenly sprayed onto the surface of farmland, a three-dimensional netted cross-linking layer is formed, a thin evaporation-preventing layer is formed on surface soil to achieve the purpose of water retention, and the cover material has the efficacy of fertilization at the same time; and polylactic acid and other raw materials all belong to environment-friendly materials so that the water-evaporation-inhibiting environment-friendly cover material used for the arid and semi-arid regions can be completely degraded into non-toxic harmless small-molecule materials in 8-12 months without microplastic residues, and the water-evaporation-inhibiting environment-friendly cover material used for the arid and semi-arid regions is safe, environmentally friendly, harmless to the environment and lowin cost.