In order to discuss the change mechanism of soil organic carbon during the recovery of desertification grassland, we studied the soil organic carbon of coarse sand, soil organic carbon of fine sand, soil organic carbon of clay and silt, heavyfraction organic carbon (HFOC), lightfraction organic carbon (LFOC) and total nitrogen under different restoration of desertification grassland in Yanchi Country, north and middle region of Ningxia (mobile dunes, semifixed dunes, fixed dunes and grasslands). The results showed that: (1) to compare with mobile dunes, soil organic carbon of coarse sand, soil organic carbon of fine sand, soil organic carbon of clay and silt in grassland, fixed dunes and semifixed dunes were increased by 67.7%, 69.8% and 212.1%; 48.8%, 35.3% and 99.9%; 33.6%, 23.0% and 48.9%, respectively. (2) The content of LFOC, the proportion of LFOC and the content of HFOC showed that mobile dunes< semifixed dunes< fixed dunes< grassland; the proportion of HFOC decreased gradually in the process of grassland restoration in desertification grassland. (3) The content of fine sand, clay and silt, HFOC, LFOC, soil organic carbon of coarse sand, soil organic carbon of fine sand and soil organic carbon of clay and silt were significantly positively correlated to the content of SOC and soil total nitrogen (TN), were significantly negatively correlated to the content of coarse sand. The content of LFOC and soil organic carbon of clay and silt have significantly effected on SOC, and the content of LFOC, HFOC, soil organic carbon of coarse sand, soil organic carbon of clay and silt have significantly effected on soil total nitrogen, which indicated that the restoration of desertification grassland is beneficial to reduce soil erosion and improved soil structure and quality.