Abstract: Objective Coal mining will cause a large area of land degradation, this work aims to solve the problems of poor soil and poor structure in open-pit waste dump Methods Taking the dump of Manlailiang open-pit mine waste dump in Ordos city as an example, the four-factor interaction experiment was designed by using four soil amendments of microbial inoculants, fly ash, coal slurry and PAM（polyacrylamide）, and the pot experiment of soil improvement and plant planting was carried out with Corethrodendron fruticosum. Results Compared with the CK, soil pH value, bulk density and sand content decreased significantly, while soil total porosity, water content, clay and silt content increased significantly, with an increase of 14.30%-28.43%, 72.94%-395.41%, 40.82%-100.00%, and 25.12%-76.62%, respectively. Soil organic matter and available hydrolysis nitrogen, available phosphorus, and available potassium content increased significantly. The increases rates were 21.31%-239.34%, 121.97%-248.97%, 134.09%-517.42%, and 19.76%-119.37%, respectively. The contents of total soil nitrogen, total phosphorus, and total potassium in soil increased significantly, and the increases rates were 118.19%-681.82%, 6.32%-234.74%, and 12.97%-63.56%, respectively. The application of four types of soil conditioners can significantly improve soil quality in mining areas, elevating from Grade Ⅵ to Grade Ⅰ. The T7 treatment shows higher effectiveness in soil improvement and enhancing the photosynthetic characteristics of vegetation growth than other treatments. Specifically, E1F3M2P0 (microbial inoculants: 0.1 g/kg; fly ash: 75 g/kg; coal slurry: 60 g/kg; PAM: 0 g/kg) is the optimal scheme for improving wind-blown sandy soil in mining waste dumps. Conclusions In this study, the four-factor orthogonal test of microbial agents, fly ash, slurry and PAM was carried out for the first time for the high-sand and low-viscosity special aeolian sandy soil in the open-pit coal mine dump in arid and semi-arid areas. The adaptation mechanism of improvement and synergy was quantitatively analyzed, and the optimal combination of low-cost PAM-free and in-situ utilization of solid waste in the mining area was screened out. It not only significantly promotes the growth and photosynthesis of C. fruticosum. but it also filled the gap in research of compound improvement of this kind of extremely sandy soil. It provides scientific and efficient technical solutions and data support that meet the requirements of green mine construction for land reclamation and vegetation restoration in mining dumps.