The work aims to address the serious impact of copper tailings (CT) accumulation on the ecological environment and explore the high-efficiency utilization of modified copper tailings as reinforcing fillers in PP/EVA blends.Silane coupling agents KH550, KH560 and KH570 were used to modify the surface of copper tailings to improve their hydrophobicity. The effects of different modified copper tailings filling on the mechanical and thermal properties of the composites were evaluated, and the dispersion of modified copper tailings in the composites and the interface bonding with the matrix were analyzed by SEM. In the copper tailings composites modified by KH570, the tensile strength reached 17.23 MPa, the flexural strength reached 28.06 MPa, and the notched impact strength reached 15.31 kJ/m2. The thermal stability was significantly improved, with the maximum degradation temperature (tmax) of 498 °C. Moreover, SEM showed that the modified copper tailings were evenly dispersed in the composites. It had good interface bonding with the resin matrix, and the stress concentration phenomenon was reduced. In conclusion, the research results provide new ideas for the high-efficiency utilization of waste copper tailings and lay a foundation for their application in resin-based composites, achieving the research goal of high-efficiency utilization of copper tailings.