Abstract: The area of poplars in China had reached 1 010.26 million hm², which ranked the first place all over the world. However, the amount of carbon dioxide which poplars can fix remains unknown. The carbon storage and density of poplars in China were measured by the volume-derived method according to the data of the seventh national forest inventory. The results showed that:the total carbon storage and carbon density of poplars in China was 261.84 Tg and 25.92 t/hm², and the carbon storage of poplar plantations and natural forests were 179.22 and 82.62 Tg. The carbon density was 23.67 and 32.65 t/hm² respectively,and the carbon storage of poplar plantations accounted for 15.9% of total plantations. In northern China, the carbon storage ofpoplar plantations was 172.94 Tg accounted for 96.5% of total carbon storage of poplar plantations.In Inner Mongolia, Henan and Shandong,the carbon storage of poplar plantations were 35.45, 24.51 and 22.42 Tg,respectively,which accounted for 55.9% of the total carbon storage of China. Carbon storage of young and middle age poplar plantations was 117.95Tg accounted for 65.9% of the total carbon storage,which had great potential for carbon sequestration. Therefore, poplar plantations in China, especially in the northern region, were the main forests for carbon sequestration.