[Objective] To explore the effects of microbial fertilizers on soil microorganism numbers and soil enzyme activities, and provide theoretical basis for improving soil environment on coal mine dump of typical steppe.[Methods] With a randomized complete block design on coal mine dump of typical steppe, two application methods and three fertilizing amounts of microbial fertilizer were set. Numbers of cultured bacteria, fungi and actinomycetes colonies were measured. Soil enzyme activity changes of urease, invertase, alkaline phosphatase and catalase were analyzed.[Results] Beneficial micro floras in soil increased to large number with the addition of microbial fertilizer. Numbers of cultured bacteria, fungi and actinomycetes colonies were all significantly higher than those of CK(p<0.05). Soil enzyme activities were improved with the application of microbial fertilizer. Soil enzyme activities of urease, invertase, alkaline phosphatase and catalase increased by 29%, 92.6%, 25.7% and 75.7%, respectively, as compared to no microbial fertilizer. There was certain correlation between numbers of bacteria, fungi, actinomycetes colonies and soil enzyme activities. Numbers of cultured bacteria, fungi and actinomycetes colonies were higher than those of other combination and soil enzyme activities were enhanced under ditching and fertilizing with larger application amount.[Conclusion] The study proved that addition of microbial fertilizer increased microorganism and soil enzyme activities significantly on coal mine dump of typical steppe, meanwhile it also improved the undisturbed soil environment and increased soil fertility.