Under the research background of resource utilization of solid wastes in the arid and semiarid regions, a new curing material was developed with the coal wastes (such as the coal gangue (CG) and coal metakaolin (CMK)), the carbide slag (CS) that is a waste material readily available in the arid region, and the ordinary Portland cement (OPC). Besides, its mechanical properties and microscopic change mechanism in curing of saline soil in the arid and semi-arid regions were discussed. Based on the laboratory experiment, the unconfined compressive strength (UCS) characteristics of curing saline soil in different ages were studied by replacing 52%, 60%, 68%, 72% and 84% OPC with CG from different mines and CG-CMK-CS, and comparison was made with the saline soil cured with 100% OPC. Then, the characteristic groups were taken for the leaching tests of harmful anions (Cl⁻ and SO₄²⁻) and microscopic tests to investigate the strength change mechanism from a microscopic perspective. The results show that the CG-CS-CMK-OPC system has a good ability of binding Cl⁻ and SO₄²⁻, with the leaching amount of Cl⁻ and SO₄²⁻ equivalent to only half of that cured by 100% OPC. Further, the hydration product tricalcium aluminate could form AFm with Cl⁻ and SO₄²⁻ in the saline soil, and thus the intra-agglomerate and inter-agglomerate pores in the system are transformed into intra-granular and inter-granular pores, reducing the hazard caused by salt in saline soil. The results of the 7d UCS test show that Shanxi Yuncheng CG curing system has the best strength, which is related to its high content of active calcium and ferroaluminum, as well as the low content of biomass. Shaanxi Yulin CG takes the second place and Shaanxi Xianyang CG has the worst performance. After replacing 52% OPC for curing saline soil with CG-CMK-CS, the compression strength of some test groups q_u exceeded that of curing saline soil with 100%OPC. Even after the replacement of 84%OPC, CG-CMK-CS-OPC can still meet the strength requirements of cement and fly ash material for highway base. Therefore, CG-CS-CMK-OPC can be used as a green, economic, environmental friendly and low-carbon curing material and promoted in the application of saline soil road subgrade engineering in the arid and semi-arid regions.