The invention relates to waterborne composite resin emulsion for fabric slurry, and belongs to the technical field of fabric adhesives. The waterborne composite resin emulsion is prepared by adding N-methyldiethanolamine and beta-hydroxyl-alpha-aminobutyric acid into a prepolymer for chain extension and cross-linking, and by adding methacryloxy propyl trimethoxyl silane, methyl methacrylate and hydroxy-propyl acrylate for second stage of polymerization. The waterborne composite resin emulsion provided by the invention is excellent in dispersibility, good in property which is not poorer than that of a polyurethane coating of a conventional organic solvent system, and particularly good in comprehensive property such as water pressure resistance, tensile failure resistance and peeling strength.