In order to improve and optimize the ecological environment in Beijing, Tianjin and surrounding areas, and mitigate the hazards of wind and sand, the Beijing-Tianjin Sand Sources Control Project (BTSSCP) was launched in 2003. The ecological effects of the BTSSCP were assessed according to the planning objects. The results showed that (1) the main parts of green ecological barrier in Beijing-Tianjin sand source regions were grassland and forest that accounted for 57.3% and 9.7% of the total area respectively, followed by cropland and sandy land that accounted for 17.2% and 6.4% of the total area respectively. (2) In 2003-2017, the area of grassland and cropland in the project region of first-stage BTSSCP decreased, while the area of forest and sand land increased. The area of the grassland, sand land and cropland in the project region of second-stage BTSSCP increased and the forest area decreased. In the past 15 years, the average vegetation coverage in the project region of BTSSCP increased by 2.3%, and the natural vegetation with increased coverage accounted for about 63% of the total area, of which the vegetation coverage of forest increased by 4.2% and the grassland increased by 2.4%. However, the average vegetation coverage in desert steppe did not increase. (3) From 2003 to 2017, the amount of soil wind erosion in the project region of BTSSCP reduced by 54%. In the total amount of soil erosion, the dust materials that can be transported remotely and directly had a direct impact on Beijing, Tianjin and Hebei were also reduced. (4) Among the factors that control soil wind erosion, the dominant grassland and sandy land contributed to 71%, which played an important role in improving the sand fixation service of the vegetation in sand source regions. In addition, the intensity of wind in spring reduced by 45% was also an important factor affecting the decrease of wind erosion in the project region of BTSSCP.