In order to improve the soil fertility in arid mining area and enrich the theory of vegetation reconstruction and ecological restoration, through the potted experiment, three common herbaceous species (Medicago sativa, Elymus dahuricus Turcz and Agropyron cristatum) in dry ore fields were planted. Combined with different concentrations of microbial fertilizer treatments, two-factor variance analysis was used to reveal the effects of fertilization levels and plant species on soil biological, physical and chemical properties, and cluster and factor analysis were used to screen the best combination of plant species and fertilization level in soil improvement. The results showed that:(1) Compared with the control group, the soil bacteria, fungi, actinomycetes, total microbial quantity, microbial biomass carbon, nitrogen, organic matter, available nitrogen, phosphorus and potassium in the test group increased significantly (p<0.05), while the microbial biomass carbon-to-nitrogen ratio and pH decreased significantly (p<0.05). (2) Plant types and fertilization levels had significant interactions on some indicators, including bacterial quantity, fungi quantity, actinomyces quantity, total microbial quantity, microbial biomass nitrogen, the microbial biomass carbon-to-nitrogen ratio. (3) The results of factor analysis and cluster analysis were basically consistent. The best treatment for soil improvement in the arid mining area was planting M. sativa and applying 20 g/kg microbial fertilizer. The application of microbial fertilizer could effectively improve soils that was poor in moisture fertility in dry mining area. With the increasing of microbial fertilizer application amount, the effect of soil improvement was better.