To improve the substandard engineering properties of saline soil in cold regions and to mitigate the environmental pollution caused by conventional calcium-based stabilization materials, ionic soil stabilizer (ISS) along with lime and fly ash are added to saline soil. Triaxial tests and discrete element numerical simulations are employed to investigate the macro-microscopic mechanical properties of the ISS stabilized saline soil in a frozen state. The results demonstrate that adding ISS significantly improves the mechanical properties of lime and fly ash-stabilized saline soil under frozen conditions. The strength of the ISS stabilized soil reaches its peak at an ISS content of 3 %, but further increase in ISS content leads to a decrease in strength. The discrete element method (DEM) indicates that a failure surface forms an angle of approximately 55 degrees degrees to the horizontal plane, with particle displacement symmetrical about the failure surface. The pore structure is significantly influenced by confining pressure during loading, and a quantitative analysis is conducted on the changes in porosity and coordination number. This research offers valuable insights for improving the undesirable engineering properties of saline soil in seasonal frozen regions using ISS and for studying its macro-microscopic mechanical characteristics. Additionally, it contributes to reducing the use of inorganic materials, thereby promoting environmental protection.