Abstract: The forest soil organic carbon stock estimation and its distributing patterns analysis is a research focus in terrestrial carbon cycle field. The forest continuous inventory plots data was used to estimate the forest soil organic carbon accumulation combined with the measured soil profile data in Guangxi. The soil organic carbon distribution characteristics in the different longitude, latitude, and altitude was analyzed. The results showed that: ① The forest soil organic carbon content was 1 852.5 Tg in which the red soil and the lateritic red soil were the main components of the organic carbon content and accounts for about 76.1%.② The organic carbon density was 12.13 kg/m² and it was below the national average level. The zonal organic carbon density was in the following order: yellow soil>red soil>lateritic red soil>latosol.③ The distribution of the overall soil carbon density in the north area were higher than the south, and the surrounding regions were higher than the middle parts. The overall trend of the organic carbon density appears “U” shape along the longitude, the latitude and the altitude. The lower area of the organic carbon density was mainly affected by the Karst area.