[Objective] In order to investigate the effect of microbial (EM) agents with fly ash dosing on the physicochemical properties of windswept soils in mine dumps. [Methods] In this study, the wind-sand soil of the discharge site of the Manlailiang open-pit mine in Ordos City was selected as the research object, and the method of field potting test was used. Based on the two-factor complete test, four levels of EM microbial agents to wind-sand soil weight ratios of 0 g/kg, 0.1 g/kg, 0.2 g/kg, 0.3 g/kg, and four levels of fly ash to wind-sand soil weight ratios of 0 g/kg, 25 g/kg, 50 g/kg, and 75 g/kg were set, and the mixing of EM microbial agents and fly ash with the sandy soil was carried out at different ratios. To study the effect of different dosages of amendments on the physicochemical properties of soil at the mine discharge site and to calculate the soil quality index. [Results] ① The application of EM microbial agents and fly ash significantly improved the soil physicochemical properties relative to T1 (CK). The effect of mixed application of EM microbial agents and fly ash on soil physicochemical properties was better than that of single application of EM microbial agents or fly ash, and the improvement of soil physicochemical properties was better with the increase of the addition of fly ash in different application ratios. ② When the EM microbial agents is 0.2g/kg and the fly ash is 75g/kg, the improvement in soil quality is most significant. The soil quality index is 0.78, which is a fertile grade with an increase of 147% compared to CK. ③ The growth and photosynthetic indicators of Corethrodendron fruticosum are closely related to the physical and chemical properties of the soil. Mantel analysis showed that the growth and photosynthetic indicators of C. fruticosum are driven by soil total nitrogen and organic matter. [Conclusion] Mixed application of two amendment materials significantly improves the soil quality of windswept soils in mine dumping sites relative to single application of amendment materials. The research results can provide guidance and technical support for soil improvement in mining areas.