The present invention discloses a film for a medicine packaging and a method of preparing the same. The film for the medicine packaging includes a polymer film layer, a graphene composite layer and a light-curable adhesive, wherein the polymer film layer is bonded with a graphene composite layer by a light-curable adhesive, the graphene composite layer includes multiple graphene layers bonded by the light-curable adhesive; and the light-curable adhesive includes a hyperbranched cationic mussel-imitated polymer including a multi-hydroxylbenzoylbenzamide ene amide monomer, a cationic monomer and a photo-responsive monomer. The present invention provides strong adhesion with reduced adhesive layer, allowing greatly increasing the number of the graphene layers in the graphene composite layer without obvious increase in the total thickness and mass. This can meet the requirements of the medicine packaging material, as it obviously lowers the film's permeation to water vapor and oxygen and significantly enhances the tensile strength.