The invention relates to a hydrothermal corrosion treatment method of a nylon film surface. A alpha crystal-form nylon 6 film or an alpha crystal-form nylon 66 film is taken as a treatment object, firstly, the nylon film is fixed flatly and has the surface contacted with water, the nylon film is kept at the constant temperature after the water is heated to the corrosion temperature, finally, cooling and drying are performed, a corroded nylon film with a concave-convex structure is obtained, and the crystal form structure of the film is not changed before and after hydrothermal corrosion treatment. The hydrothermal corrosion treatment method adopts water as a solvent, instable non-crystalline parts on the surface of a nylon material are damaged by use of the characteristics of high water molecule movement speed, low density, small viscosity and high flowability under the hydrothermal condition, meanwhile, the water temperature is controlled in a specific range, the crystallized parts are ensured to be not damaged, and a crystalized structure on the surface of a polymer is sufficiently exposed. Moreover, the method is simple in process and low in cost, cannot pollute the environmentand can realize safe and green production.