Abstract: It is important to accurately assess carbon sequestration ability and trends in forest ecosystems to achieve sustainable forest carbon sinks. Based on forest inventory data of four times in China, the carbon storage and carbon density of forest vegetation in Yangtze River Basin were assessed by means of the regression equation between vegetational biomass and volume, and with the carbon fraction of dry matter. The results show that the carbon storage of forest vegetation increased from 1 345.30 Tg to 1 924.98 Tg during the period of 1989-2008 in Yangtze River Basin, with an average annual growth rate of 2.15%, which was 0.29 percentage point more than that of the mean increment of China, implying that the potential of carbon sink of forest in Yangtze River Basin was increasing. Correspondingly the average carbon density of forest vegetation was 42.25, 40.34, 41.00 and 41.42 Mg·hm^-2, respectively. The carbon storage of forest vegetation mainly concentrated in young, middle-aged and near-mature forests, and the contribution of them to the carbon stock of the stands exceeded 85%, indicating that the carbon sequestration potential of forest vegetation was large. Carbon storage of forest vegetation was mainly distributed in natural forests, accounting for more than 78% of the total carbon storage in the same period. However, the carbon storage capacity of plantations was gradually increasing. The proportion of carbon storage in plantations to the forest carbon storage in the same period showed an increasing trend, and the carbon density of plantations was obviously smaller than that of natural forest, indicating that plantations would play an important role in sequestrating carbon by forest vegetation. The middle and upper reaches of the Yangtze River were the major contributors to the carbon storage of forest vegetation in the basin, accounting for more than 96% of the carbon storage of forest vegetation in the whole basin. Furthermore, the results also show that forest vegetation in Yangtze River Basin played an important role in the national forest carbon storage and enhancement of the national forest carbon sequestration function.