Abstract: The study selected desertification combating area of Baijitan in Ningxia, through field investigation, sampling and laboratory experiment, measured and analyzed the physicochemical property of aeolian sandy soil of mobile sand dune, semi-mobile dune and fixed dune, and preliminarily attained the following conclusions: soil moisture were all lower, and the mean value of soil water of the fixed dune ＞ semi-mobile dune ＞ mobile sand dune. The grain composition of sandy soil was dominated by fine sand, followed by middle sand, and the content of mighty fine sand was very low. A small amount of coarse sand was on the surface of mobile sand dune, and both semi-mobile dune and fixed dune had no coarse sand. And a small amount of silty sand was on the surface of fixed dune. Soil bulk density of sandy soil decreased little by little from surface down, and the soil bulk density of mobile sand dune and semi-mobile dune was approximate, the soil bulk density of the surface of fixed dune was lower. The soil nutrients of mobile sand dune, semi-mobile dune and fixed dune were all very low and approximate, and the vertical variation had no obvious rule and was unstable.