OBJECTIVE: To study the correlation between plant diversity and the physicochemical properties of soil microbes. METHODS: The determination of the chemical properties of farmland soil in the research area can be achieved by potentiometer method, automatic analyzer method, molybdenum antimony anti-colorimetric method and gas chamber method. Based on the determination results, the relationship between plant diversity and soil microbial physical and chemical properties in the national nature reserve in rocky desertification area can be analyzed. RESULTS: The physical and chemical properties of soil in different grades of rocky desertification were significantly different. With the increase of rocky desertification, soil physical and chemical properties showed a response process from degradation to improvement. Soil organic matter, nitrogen, capillary water holding capacity, bulk density and porosity were significantly correlated with plant diversity, which played an important role in improving soil physical and chemical properties and promoting the restoration of plant diversity. Factor analysis showed that plant diversity at different levels in national nature reserves had different correlation with soil physical and chemical factors at different levels. The ratio between the significant correlation factors and the number of plants showed that the diversity of trees was greater than that of shrubs, and the diversity of shrubs was greater than that of herbaceous plants. Tree plant diversity factor plays a leading role. CONCLUSION: With the proposed method the physicochemical properties of soil microbes can be effectively studied.