To better understand the effects of forest succession on soil microbial activity, a comparison of soil microbial properties and nutrients was conducted between three forest types representing a natural forest succession chronosequence. The study compared a pine(Pinus massoniana) forest(P_F), a pine and broadleaf mixed forest(M_F) and an evergreen broadleaf forest(B_F), in the Yingzuijie Biosphere Reserve, Hunan Province, China.Results showed that soil nutrients in the M_Fand BFplots were higher than in the P_Fplots. The range in microbial biomass carbon followed a similar pattern with B_Fhaving the greatest values, 522–1022 mg kg~-1, followed by M_F368–569 mg kg~-1, and finally, P_F193–449 mg kg~-1. Soil nutrients were more strongly correlated with microbial biomass carbon than basal respiration or metabolic quotient. Overall, forest succession in the study site improved soil microbial properties and soil fertility, which in turn can increase primary productivity and carbon sequestration. To better understand the effects of forest succession on soil microbial activity, a comparison of soil microbial properties and nutrients was conducted between three forest types representing a natural forest succession chronosequence. The study compared a pine (Pinus massoniana) forest (P_F), a pine and broadleaf mixed forest (M_F) and an evergreen broadleaf forest (B_F), in the Yingzuijie Biosphere Reserve, Hunan Province, China. Results showed that soil nutrients in the M_Fand BFplots were higher than in the P_Fplots. The range in microbial biomass carbon followed a similar pattern with B_Fhaving the greatest values, 522-1022 mg kg ~ -1, followed by M_F368-569 mg kg ~ -1, and finally, P_F193-449 mg kg ~ -1. Soil nutrients were more strongly correlated with microbial biomass Overall, forest succession in the study site improved soil microbial properties and soil fertility, which in turn can increase primary productivity and carbon seque stration.