Abstract: Although soil microbial biomass only accounts for 5% of soil organic carbon, it plays an important role in the process of organic matter decomposition and nutrient cycling. By using the temporal-spatial substitution method, five different stand ages of Cunninghamia lanceolata plantation, such as 5-year-old, 8-year-old, 21-year-old, 27-year-old and 40-year-old were selected in the subtropical region of China. The content of soil dissolve organic carbon and dissolve organic nitrogen and the content of soil microbial biomass carbon and nitrogen were determined to explore the changing characteristics of soil labile carbon and nitrogen components in Cunninghamia lanceolata plantation at different stand ages. The results showed that the content of soil ammonium nitrogen in the 5-year-old stands was significantly higher than that in the 8-year-old stands and 40-year-old stands in Cunninghamia lanceolata plantations of different ages. The contents of dissolve organic carbon (DOC) in the 27-year-old and 40-year-old stands were significantly higher than that in the 5-year-old and 21-year-old stands. The microbial biomass carbon (MBC) content of the 5-year-old Cunninghamia lanceolata was significantly lower than that of other stand ages, and the microbial biomass nitrogen (MBN) content of the 21-year-old Cunninghamia lanceolata was the lowest. The soil nitrate nitrogen and total carbon were correlated with soil dissolve organic carbon and nitrogen, and the soil microbial biomass carbon was closely related to soil total carbon and total nitrogen. The results indicated that the size of soil microbial carbon and nitrogen pools in Cunninghamia lanceolata plantation at different stand ages may be related to soil nutrients.