Abstract: China is one of the most serious desertification countries in the world, the desertification area covered 1.72×108 km2, involving 30 provinces (regions), which accounted for about 17.93% of the territory area by the end of 2014. Hobq Desert covering about 1.86×104 km2 is the seventh largest desert in China, which locates in the north of Ordos Plateau, and it is one of the important sandstorm source threatening the Beijing, Tianjin and Hebei urban regions where the linear distance from the Hobq Desert is about 800 km. Moreover, in the eastern part of the Hobq Desert, ten tributaries of the Yellow River cross the desert, and these are called the Ten Tributaries. According to the research results, the annual sediment by floods through the Ten Tributaries could reach as high as 2.37 × 108 t. The sediment causes serious silting in the Yellow River. Therefore, it very urgently needs to control the sandy desertification of Hobq Desert. Generally speaking, there are three kinds of sand-fixation techniques, engineering sand-fixation technique, biological sand-fixation technique and chemical sand-fixation technique. Chemical sand fixing technique sprays chemically bonded materials on the sand dunes to form a consolidation layer to prevent the wind erosion. In this research, we aimed to develop efficient, environmental and low-cost sand-fixing agent in order to provide new material and technical reserve for sandy desertification control and ecological restoration in Hobq Desert. GS-3 ecological sand-fixing agent is modified vinyl acetate polymer (cationic P (VAc-BA-DMC) emulsion), which is non-toxic, tasteless, safe, environment-friendly, good combination and cohesiveness. After spraying, it can form hard, water holding and breathable consolidation layer on the surface of sand. It is suitable for mechanized operation and can be combined with biological sand-fixation measures. Through studying the physical and chemical properties of GS-3 ecological sand-fixing agent, the results showed that: 1) The consolidation layer of GS-3 had great permeability, the compressive strength was over 2 MPa, the hardness reached more than 40 mm, the quality varied slightly, and the resistance to wind erosion was excellent. 2) The GS-3 had great inhibited effect on the high temperature surface in the summer, the soil moisture was maintained effectively. The soil temperature at 0-5 cm depth was decreased by 8.1 ℃ in July. The soil moisture at 0-5 cm depth was 2.8 times higher than the control group in August. 3) The thermal insulation, air permeability, moisture retention and resistance to wind erosion of the GS-3 was of great significance to the plant growth. 4) The 4% GS-3 was the best for sand fixation, but the vegetation coverage and biomass of the 3% GS-3 were the maximum (2.4 times and 4.1 times than the control group). The price of the 3% GS-3 ecological sand-fixing agent is about 2 RMB per square meter in the Hobq Desert, but the high-banded salix psammophila sand-barriers costs about 3 RMB per square meter. With the progress of production technology, the price of the GS-3 ecological sand-fixing agent will continue to decline, which is conducive to popularization and application in large areas. Considering the cost and the effect, the 3% GS-3 was the ideal sand fixation material.