Abstract: The soil labile carbon is one of the important components of the global carbon cycle. The variations of soil total organic carbon(TOC), water soluble organic carbon(WSOC), readily oxidation carbon (ROC)and their correlations with basic physicochemical properties at four plantations were examined in south area of Jiangsu province. Our results showed that the soil TOC concentration ranged in order as follow: Quercus acutissima>Cunninghamia lanceolata>Phyllostachys pubescens>Pinus elliottii. The soil WSOC concentration ranged in order as follow: Ph. pubescens>C. lanceolate>P. elliottii>Q. acutissima. The soil ROC concentration ranged as follow: Q. acutissima>Ph. pubescens>C. lanceolata>P. elliottii. The WSOC/TOC, ROC/TOC ratios were varied. There was significantly correlation among AOC(WSOC & ROC)and TOC, TN, respectively. Meanwhile, there was no significantly correlation between AOC and other soil basic physicochemical properties. Our study indicated that the soil organic carbon of broadleaved plantations was higher than that in the coniferous plantations, and Ph. pubescens might play an important role in carbon cycling of forest ecosystems. However, the stabilization of soil carbon storage of them did not obvious different.