The high-barrier food preservation bag film is a seven-layer composite film, characterized in that, from the outside to the inside, they are: the first nylon layer, the ethylene/vinyl alcohol copolymer layer, the second nylon layer, and the acid anhydride modified high-density poly Ethylene polymer layer, first acid anhydride modified linear low density polyethylene polymer layer, second acid anhydride modified linear low density polyethylene polymer layer, metallocene polyethylene layer; the first nylon layer is corona The first nylon layer is 30% long glass fiber reinforced PA6, the density of the first nylon layer is 1.34g/m, the tensile strength is 1550×10Pa, the bending strength is 1467×10Pa, and the impact strength is 142J /m, the heat distortion temperature is 212°C, the elongation rate is 2.2%, and the thickness is 5-6μm; the second nylon layer is 30% short glass fiber reinforced PA6, and the density of the second nylon layer is 1.22g/ m, the tensile strength is 970×10Pa, the bending strength is 1885×10Pa, the impact strength is 68J/m, the heat distortion temperature is 182℃, the elongation is 3.5%, and the thickness is 3-4μm; the ethylene/vinyl alcohol copolymer The ethylene content in the ethylene/vinyl alcohol copolymer of the material layer is 32%; the degree of hydrolysis of the ethylene/vinyl alcohol copolymer layer is 92%-94%, the viscosity diameter is 170-190 mesh, and the Vicat softening point is 83°C-86 ℃, density 0.958g/m, melt index 58g/10min, thickness 8-10μm; the density of the acid anhydride-modified high-density polyethylene polymer layer is 0.951/cm, and the acid anhydride-modified high-density polyethylene The thickness of the polymer layer is 1.5-2.5 μm; the comonomer type of the anhydride-modified linear low-density polyethylene polymer of the first acid anhydride-modified linear low-density polyethylene polymer layer is hexene-1 type The thickness of the first acid anhydride-modified linear low-density polyethylene polymer layer is 1-2 μm; the second acid anhydride-modified linear low-density polyethylene polymer layer is anhydride-modified linear low-density polyethylene The comonomer type of the polymer is octene-1; the thickness of the second acid anhydride modified linear low-density polyethylene polymer layer is 1-2 μm; the thickness of the metallocene polyethylene layer is 2-5 μm The thickness of the seven-layer composite film is 25-28 μm.