With comparative method,the carbon storage and its distribution pattern of five species plantations system located at Shaopin Experimental Farm of Experimental Centre of Tropical Forestry in Pingxiang, Guangxi, China were investigated and studied. The purpose was to evaluate the potential carbon sinks of large sized trees in plantations, and to provide more perspective about commercial forest plantations that are being adaptively managed for timber production objectives in conjunction with carbon storage objectives. The results show that the carbon storages of different species plantation systems had greater differences under similar habitat, same stand age (27-year-old) and same management history, among them, Michelia macelurei stand had the greatest capacity to store carbon, its carbon storage was 359.43 t/hm~2, the next was Mytilaria laosensis stand, being 319.80 t/hm~2, carbon storages of Castanopsis hystrix stand, Pinus massoniana stand and Mesua ferrea stand was 225.87 t/hm~2, 222.43 t/hm~2 and 207.81 t/hm~2, respectively and theirs difference was insignificant;The majority of carbon storage was found in the tree layer and soil layer, accounting for over 95%of the total carbon storage of ecosystems;Litter floor contributed 0.87%~4.29% carbon storage to the ecosystems. Under-story shrubs and herbs were in small contribution to ecosystem carbon storage, up to only 0.5%;Carbon storage of tree layer showed larger differences among different species forests, M. laosensis stand was the highest, for 188.09 t/hm~2, followed by M. macelurei stand, for 176.44 t/hm~2, and then followed by C. hystrix stand, being 102.56 t/hm~2, the Pinus massoniana stand and the Mesua ferrea stand were the lowest, for 84.59 t/hm~2 and 84.01 t/hm~2. Different species of trees had the different organ carbon allocation, but they are all the same law, that the trunks was the highest, followed by the roots or the branchs, and then followed by the barks, the leaves was the lowest;Carbon storage of shrub layer and herb layer was 0.036 t/hm~2 ~1.163 t/hm~2 and 0.027 t/hm~2~0.913 t/hm~2, that of litter floor was between 9.54 t/hm~2 and 2.37 t/hm~2;In the case of the soil, the carbon was stored mainly in the 0 to 50 cm layer, which accounted for 61.33%to 64.69%of the carbon stored in 100 cm depth of the soil, carbon storage declined as the depth of soil increased;The carbon storage in the 0 to 100 cm soil layer of M. macelurei stand was the greatest, 179.59 t/hm~2, higher than that of the other stands, and that of M. laosensis stand, C. hystrix stand, M. ferrea stand and P. massoniana stand was all most the same, about 120 t/hm~2. The findings suggest that the plantations in lower subtropical China have high biomass productivity and higher carbon storage capacity, particularly in M. macelurei stand and M. laosensis stand, because of abundant light and heat resources. Therefore, the plantations in low subtropical China can be into develop into high carbon sequestration artificial timber base, thus playing an important role for Chinas forestry response to climate change in current and future.