Abstract: The polyethylene grafted acrylic acid (PE-g-AAC) composite films with different grafting ratios were prepared by electron beam pre-irradiation. The study explored the effect of grafting ratio on the performance of composite membranes. The results show that the grafting ratio and water absorption ration of PE-g-AAc composite membrane increase with the increase of acrylic acid concentration. When the volume fraction of acrylic acid is 15vol%, the maximum grafting ratio is 263%, and the maximum water absorption ratio is 635%. The area resistance of PE-g-AAc composite membrane decreases with the increase of acrylic acid grafting ratio. When the grafting ratio is 30.4%, the area resistance of PE-g-AAc composite membrane decreases from 45000 mΩ·cm² (without grafting) to 870.9 mΩ·cm². When the grafting ratio is 263%, the area resistance is 70.1 mΩ·cm². The tensile strength first decreases and then increases with the increase of grafting ratio. The maximum tensile strength reaches 45.6 MPa when the grafting ratio is 262%. The elongation at break decreases with the increase of grafting ratio. The grafting ratio result shows that under certain absorbed dose and reaction conditions, the higher the concentration of acrylic acid, the greater the ratio of chain growth rate to chain termination rate, and the greater the degree of acrylic acid polymerization. The results on water absorption and area resistance study show that, acrylic acid can effectively increase the surface energy of the polyethylene film, enhance the hydrophilicity, increase the ion conductivity, and reduce the area resistance of the polyethylene film. This study will provide direct reference value for the preparation of polyethylene grafted acrylic membrane for battery separator and ion exchange membrane.