Objective To prevent postharvest fruit decay and extend shelf life, a robust, water-resistant, and self-healing multifunctional edible fresh-keeping film was proposed.Methods The edible fresh-keeping film's microstructure, chemical structure, physicochemical properties, mechanical properties, and its effects on the shelf life of bananas were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffractometer (XRD), texture analyzer, and rheometer.Results The monomers within the edible film are cross-linked via hydrogen bonds, ester bonds, and electrostatic interactions, forming an irregular network structure on the surface. The film exhibits an elongation at break of 71.73% and a mechanical strength of 51.48 MPa, as well as good hydrophobicity and water vapor and oxygen barrier properties. Postharvest banana fresh-keeping experiments indicate that the edible film effectively reduces weight loss and softening, delays pulp ripening, and extends the shelf life of bananas to eight days.Conclusion The multifunctional edible film can be used in food packaging to extend the shelf life of postharvest fruits.