The invention provides a degraded mulch film containing nanometer level TiO2 photocatalysis, water, oxidation and biological degradation technologies, and relates to an agricultural mulch film. The mulch film is mixed from aliphatic polyester, polylactic acid, starch / polyvinyl alcohol, a modified plant straw, a film forming agent and a surfactant, and the mulch film comprises three layers, the mulch film middle layer contains the nanometer level TiO2 photocatalyst and a hydrolytic agent which are mixed in proportion; the upper layer is sprayed with a paint containing an oxidation degradation agent; the mulch film lower layer is sprayed with a fertilizer, a microelement fertilizer, a pesticide and a herbicide or the like which are mixed in proportion and are needed by plant growth; The three-layer mulch film provided by the invention can decay and decompose by itself, integrates pesticide, fertilizer and pesticide without residual, and comprises nanometer level TiO2 photocatalysis, water, oxidation and biological degradation technologies. The invention has the advantages of wide raw material sources, low cost, various degradation modes and fast degradation speed, and is suitable for different crop growths.