Abstract:In Shapotou districts of southeastTengger Desert, we selected the flow sand, 4 and 30 years sand fixing areas within straw checkerboard as the research plots to study the soil properties and fractal characteristics during the process of forestation and sand fixation by straw checkerboard across seasons. The results showed that:(1) Soil moisture content and soil pH were affected by both timing of sand fixation and seasonal variations. (2)Soil electrical conductivity of the flow sand, the 4 year and the 30 years sand fixing vegetation area was 77.84~82.34, 86.04~114.68 and 113.80~168.66 μS/m, respectively, and soil organic carbon of the three kinds of plots was 0.86~1.74, 1.30~1.52 and 7.96~17.36 g/kg, respectively, and soil total nitrogen was 0.18~0.32, 0.24~0.26, and 0.44~0.78 g/kg, respectively.(3) Coarse sand was found only in the flow sand, and the content was 0.50%~0.53%. Medium sand content of the flow sand, the 4 year and the 30 years sand fixing vegetation area was 40.42%~43.82%, 14.36%~17.17% and 12.01%~14.75%, respectively, and fine sand content was 55.44%~58.84%, 80.15%~83.19% and 42.55%~53.30%, respectively, and very find sand was 0.24%~0.31%, 2.45%~3.33% and 15.85%~21.35%, respectively. Clay and silt were found in the 30 years sand fixing vegetation area, and the content was 0.84%~1.33% and 15.16%~22.75%, respectively. (4) There was a negative correlation between coarse sand and soil electrical conductivity(P<0.05), and fine sand and medium sand both showed significant negative correlation with electrical conductivity, organic carbon, total nitrogen and carbon-nitrogen ratio(P<0.01). Clay, silt and very fine sand all showed significant positive correlation with soil electrical conductivity, organic carbon, total nitrogen and carbon-nitrogen ratio(P<0.01). (5)The soil fractal dimension was 0~3, soil fractal dimensionof the flow sand, the 4 year and the 30 years sand fixing vegetation area was 0.55~0.82,1.57~1.67 and 2.37~2.59, respectively. (6)There was a negative correlation between soil fractal dimension and coarse sand, medium sand(P<0.05), which had significant positive correlation with clay, silt, and very fine sand (P<0.01), but had no correlation with soil fine sand (P>0.05). It was concluded that the stabilization of flows and by straw checkerboard and artificial forestation and sand fixation in southeast Tengger Desert could improve soil texture, promotethe better development of soil physical-chemical properties and the improvement of soil quality, and prevent and control desertification.