Abstract: The massive accumulation of industrial solid waste semi-coke ash (SCA) will cause damage to local ecological environment. To promote the large-scale consumption of industrial solid waste semi-coke ash and fabricate low-cost shape-stable phase change composites (SSPCCs), semi-coke ash was innovatively proposed as a skeleton material to fabricate the SSPCCs. To evaluate the feasibility of the semi-coke ash as the skeleton material of the SSPCCs, eight NaNO₃/semi-coke ash SSPCC samples with different mass ratio of the semi-coke ash to NaNO₃ were fabricated. The key performance of the NaNO₃/semi-coke ash SSPCCs were investigated by the differential scanning calorimetry, laser flash analysis, scanning electron microscopy, constant speed pressurization method and X-ray diffraction. Results show that the sample NaNO₃/SCA-50 without visual leakage and deformation holds the optimal mass ratio 5:5 of the semi-coke ash to NaNO₃ with the thermal energy storage capacity of 338.24 J/g ranging from 100 to 380℃ and the mechanical strength of 96.98 MPa. After 4027 heating/cooling cycles, the sample NaNO₃/SCA-50 keeps good thermal stability and chemical compatibility, which indicates that the semi-coke ash is feasible for the SSPCCs fabrication, and provides a new way for recycling the resource of the solid waste semi-coke ash.