【Objective】 Thinning is an important management measure in plantation forest management, which can change the growth environment and affect the growth, productivity and carbon storage of the forest stands. As an important tree species for afforestation in southern China, Chinese fir occupies an indispensable position in forestry production. Therefore, studying the short-term impact of different thinning intensities on carbon storage in Chinese fir plantations helps to optimize forest management measures, and accurately evaluate the short-term effects of thinning on the biomass and carbon storage, which is important in the development of carbon sink forestry, and can provide a basis for improving carbon sink capacity.【Method】 The 11-year-old Chinese fir plantations in Guanzhuang State Forest Farm in Sanming City, Fujian Province, with consistent slopes, slope positions and soil conditions were selected for research. The experiment was designed according to a random block design with three levels of thinning intensity with light thinning (31%, LIT, 2 250 plants/hm² in post-cutting stand), moderately intensive thinning (45%, MIT, 1 800 plants/hm² in post-cutting stand),and highly intensive thinning (63%, HIT, 1 200 plants/hm² in post-cutting stand). A total of nine 20 m×20 m sample plots were set up, and soils from different soil layers in a 1 m section were collected. In the sample plot, the biomass of the tree layer was estimated using the biomass regression equation, and the biomass of the understory vegetation and litter were measured. The carbon content of the vegetation and soil was measured using an element analyzer, and the carbon storage was estimated based on the carbon content. The carbon storage and distribution pattern of each component in the ecosystem were examined after three thinning treatments. The carbon storage of each component of the ecosystem during the growth of the Chinese fir after three thinning treatments was analyzed to evaluate the effects of thinning on the carbon storage of the Chinese fir plantation.【Result】 Three years after thinning, the carbon storage of the tree layer and the soil layer decreased with the increase in thinning intensity. The carbon storage of the tree layer for the LIT, MIT, and HIT plots was 66.16, 58.77, and 49.71 t/hm², respectively. The carbon storage of the shrub layer and herb layer significantly increased with the increase in thinning intensity, accounting for 0.03%-0.19% and 0.01%-0.67% of the carbon storage of the ecosystem, respectively. There was no significant effect on the carbon storage of the litter layer, and the litter layer carbon storage accounted for 2.87%-4.32% of the ecosystem carbon storage. The soil carbon storage decreased with the increase in thinning intensity, and the soil organic carbon storage was significantly different between different thinning treatments (P < 0.05). The soil carbon storage from the HIT treatment reduced 32.07% and 1.03% compared with LIT and MIT treatments. Three years after thinning, the carbon storage significantly decreased with the increase in thinning intensity (P < 0.05). The total carbon storage of the LIT, MIT and HIT plots was 173.85, 161.12 and 121.73 t/hm², with the sum of the carbon storage of the tree layer and soil layer accounting for more than 90.00%. It indicates that the tree layer and soil layer are huge carbon pools, and thinning will reduce the total carbon storage in short-term in the ecosystem.【Conclusion】The carbon storage of the arbor, litter layer and soil layer in the Chinese fir plantation short-term decreased with the increase in thinning intensity after thinning, while the carbon storage of the shrub and herb layer increased with the increase in thinning intensity, indicating that the intensity of thinning increased after three years, and that the experimental forest land is still in the recovery period. The research revealed that thinning of Chinese fir plantations will reduce the total carbon storage of the ecosystem in short-term, provide a scientific basis for the carbon sink and sustainable management of plantations in the study area.