By taking the dump site of Nortel Shengli open-pit mine as the research area, 5 different planting modes of Caragana korshinskii monocropping, Caragana korshinskii and Astragalus adsurgens mixed cropping, Astragalus adsurgens monocropping, Astragalus adsurgens and alfalfa (Medicago sativa) mixed cropping, and alfalfa monocropping were set up. With inoculation (Funneliformis mosseae) and control as two treatments, classical statistics was used to analyze plant root morphology, soil physicochemical properties, and related enzyme activities. The results show that the total root length of the inoculated plants under the modes of Caragana korshinskii and Astragalus adsurgens mixed cropping and Astragalus adsurgens and alfalfa mixed cropping increased by 203.74% and 83.84%, respectively, compared with the control, indicating that inoculation in mixed cropping mode is more suitable for the growth environment of mining dump, and the total root length of plant root system is increased. The soil organic matter inoculated under the mixed cropping mode of Caragana korshinskii and Astragalus adsurgens was 22.92 g/kg, an increase of 89.58% compared with the control. The inoculation under the mixed cropping mode of Caragana korshinskii and Astragalus adsurgens promoted the accumulation of soil organic matter, which was beneficial to the soil improvement of mining area. The contents of soil urease, easily extractable glomalin-related soil protein, and total glomalin-related soil protein were higher to different degrees in the modes of Caragana korshinskii and Astragalus adsurgens mixed cropping and Astragalus adsurgens and alfalfa mixed cropping than in other monocropping modes. Inoculation under mixed cropping mode in the field can effectively promote plant growth, improve soil texture, and has significant ecological effects, which is of great significance to maintaining the stability of mining ecosystem.