This research focused on four same-succession-age forest communities under different management practices in the Northeast of China, including the natural secondary forests (WB), the mixed forests (MA) that the Korean Pine (Pinus koraiensis) was artificially regenerated under the WB canopy, the selective logged Korean Pine forests (SK) were formed by that all the successional pioneer species in MA were selected logging, thinning Korean Pine forests (KT) formed by timely thinning of SK. The management gradient of the four forest communities has gradually increased. To quantify vegetation carbon density (VC) and its distribution pattern, and to explore the effect mechanism of forest management on vegetation carbon density and its distribution pattern, we used a combination of site inventory and allometric growth equation method, determined the community characteristics such as biodiversity, the ratio of needle to broadleaf species, and soil nutrient characteristics such as nitrogen and phosphorus density. The results showed that there were significant differences in carbon density among the four management practices for successional pioneer species (PI), the late-successional dominant species (LT), and the understory vegetation (UC). Among them, LT increased from 9.39 t/hm² in WB to 107.02 t/hm² in KT. However, the carbon density of associated species had no significant differences among the four management practices, with a fluctuation range of 8.41 to 14.89 t/hm². The VC was significantly increased with the intensity of forest management, with a fluctuation range of 96.34-135.40 t/hm². The mean annual increment of VC fluctuates between 1.50-2.11 t hm^-2 a^-1, and there were significant differences among management practices. There were significant differences in the proportion of PI, LT, and UC to the VC of vegetation among the four management practices. The proportion of PI gradually decreased, while the proportion of LT significantly increased (from 14.0% of WB to 82.2% of KT) with management gradient. There were significant differences in the ratio of vegetation residues to living biomass carbon density (the range was 0.05-0.13), and belowground to aboveground carbon density (the range was 0.24-0.30) among the four management practices. There was significant negative correlation between the carbon density of overstory and tree species diversity, while there was significant positive correlation between the carbon density of understory and tree species diversity. And there was no significant correlation between VC and soil nitrogen and phosphorus storage. These indicated that under the same climatic conditions, community characteristics and tree species composition were important factors determining the differentiation of vegetation carbon density, and active forest management by increasing the proportion of late-successional dominant species significantly enhanced the vegetation carbon density and carbon sequestration of secondary forest in the Northeast China.