Abstract: Tailings is a type of misaligned resource that has received widespread attention for comprehensive utilization. Tailings can serve as carriers for phase change materials (PCMs) in thermal energy storage applications with rich pore structures and relatively large specific surface areas. In this study, a novel composite phase change material (CPCM) was prepared by a hybrid sintering method to combine gold tailings−fly ash mixture as the base material with solar salt as the phase change material for thermal energy storage. The chemical compatibility of the CPCM analyzed by X−Ray Diffraction (XRD). And the micro−structure, thermal conductivity performance of the CPCM were characterized by Scanning Electron Microscopy (SEM), Differential Scanning Calorimeter (DSC) and Laser Flash Analysis (LFA). The results showed that when the content of gold tailings was 22.5%, fly ash was 22.5% and solar salt was 55%, the composite has the best properties and good chemical compatibility. Furthermore, the maximum latent heat of the CPCM was 53.8 J/g, its thermal conductivity was 0.27 W/(m·K), and reached a mechanical strength of 33.7 MPa. Critically, the CPCM specimens had good cycling reliability after 100 thermal cycles. In conclusion, the utilization of tailings to prepare phase change energy storage materials was considered to be feasible and provided a new avenue for the resource utilization of tailings.