Changes in forest land use contribute to the carbon source in most tropical regions due to large-scale deforestation but are poorly documented for arid forest ecosystem. According to "Guidelines for Land Use, Land-use Change and Forestry" documented by IPCC, we estimated sources and sinks of carbon from forest land use change between 1975 and 2005 in Xinjiang, China. The results indicated that: (1) the carbon stock of forest ecosystem in Xinjiang is 720.02 Tg in 1975, whereas the vegetation carbon stock is 191.20 Tg, and soil carbon stock is 528.82 Tg; (2) Generally, the effect of forest land use change in Xinjiang performed as a carbon sink, with a total carbon sequestration of 48.15 Tg, and increased by 6.69% compared with the total carbon stock of 1975. The accelerated afforestation led to a strong carbon sequestration (54.24 Tg), while the deforestation showed a main carbon source, releasing 5.42 Tg. The woodland transferring performed as a weak carbon source, releasing 0.66 Tg; (3) We recommend that some efficient measures should be taken on raising the quality and quantity of forest resources in the future to enhance the forestry carbon sequestration in Xinjiang. Therefore, this can offset the carbon loss from industrial activities so as to provide sufficient space for the sustained and healthy economic development in Xinjiang. This study will be conducive to further deepen the understanding of the influence of human activity on regional carbon balance.