Soil microbial biomass carbon (MBC,Microbial Biomass Carbon) is an important component of soil microbial biomass and one of the important indicators of soil fertility changes. The fertile soil of the Hani terraces plays an important role in the maintenance and circulation of the Hani terrace ecosystem. Taking Hani terraced water source area (arbor forest, shrub forest, grassland) and terraced fields as research objects, four different land use types of 0-20, 20-40 and 40-60 cm were determined by chloroform fumigation method. The soil MBC was analyzed and its relationship with seasonal changes, aboveground vegetation and soil physical and chemical properties was analyzed. The results showed that the three soil layers of the four types of land use type MBC were the highest in the arbor forest, followed by the shrub forest, grassland and terraced fields, and the soil MBC content of the four land use types decreased with the increase of the soil depth. The MBC content of 0-20 cm soil layer in arbor forest is 3.19 times that of 40-60 cm soil layer. The soil MBC content of the four land use types had obvious seasonal changes, and the overall pattern was high in summer and low in winter. The correlation analysis showed that the diversity index, coverage, dominant species height, litter layer thickness and the soil MBC of each soil layer had strong correlations with different land use types. The soil MBC was positively correlated with soil organic carbon and soil porosity, and negatively correlated with soil bulk density. The vegetation growth, soil organic carbon and porosity content and seasonal variation are the main factors leading to differences in soil microbial biomass carbon in different land use types.