The effect of LUCC on carbon budget of terrestrial ecosystem is one of the important contents in the research field of global climate change. In this study, the monitoring data of land use, land use change and forestry carbon sink were used to research the land use change and its carbon sink effects in Yanchi County during the period from 2005 to 2013. The results are as follows: ① The land use level in the county was below the average level of China,and its transfer activities occurred mainly among other land use types, such as the farmland,grassland and forest land; ② The carbon reserve of vegetation in the county was increased by 23.96%, the soil carbon reserve was decreased by 0.30%,and the total carbon sink value was decreased by 5.00 * 10~9 US dollars during the period of 2005 - 2013; ③ Enlargement of forest land was the main reason for the increase of carbon reserve in Yanchi,and the change and management of grassland were the important factors that affected the soil carbon reserve; ④ From the analyzed results of land use change,carbon reserve and its price driving, it could be found that the biggest effect on the carbon reserve in Yanchi was the transfer of land use types. Therefore, the carbon reserve in the county may be improved by considering other land use types in the future development. Moreover, the grassland and forest land management would be an important cause of carbon source /sink change in the county.