The invention relates to an agricultural liquid mulching film and a production method thereof. The agricultural liquid mulching film is prepared by taking sweet potato starch, white sugar, industrial alcohol, a reinforcing agent, a flocculating agent, an emulsifier, a filming agent, a stabilizing agent, a water retaining agent, a cross-linking agent, a heat-preservation agent, a surfactant, a soil conditioning agent and water as raw materials through the steps of raw material gelatinization, condensation, stirring, copolymerization, reaction, cross-linking and the like. Compared with other similar products in the market, the agricultural liquid mulching film has the characteristics of large tensile strength, breakage elongation degree and high water resistance, is relatively low in cost, relatively good in market prospect, and easy to popularize and apply in a large scale.