The invention discloses a making method of a high-strength solid electrolyte bionic ultrathin film. The method comprises the following steps: (1) preparing graphite oxide through a Hummers technology; (2) preparing sulfonated polyvinyl alcohol; and (3) making the composite film. The composite film comprises 40-70% by mass of an inorganic material and 30-60% by mass an organic material, the inorganic material is a mixture of graphite oxide and montmorillonite, and the organic material is sulfonated polyvinyl alcohol. The internal structure of the obtained high-strength solid electrolyte bionic film with two-dimensional fast proton transfer channels is uniform and has no defects, the ion exchange capacity in the film is 1.12 mmol.g<-1>, the ion conductivity at room temperature is 0.0921-0.222 S cm<-1>, the water absorption rate is 18.7-38.6%, the mechanical strength is 180.7-287.7 MPa, and the Young's modulus is 10.72-13.74 Gpa.