Using TM satellite image data in 1989,2000,and 2005 as remote sensing information source,dynamic changes of sandy desertification in Pishan area of Xinjiang during 1989—2000 and 2000—2005 are analyzed by establishing a scientific system to classify the types of sandy desertification land,calculating the areas of these lands in different years and examining the conversions among these types of land during the periods. The features of the range,speed and spatial variation of various types of sandy desertification land are revealed. The evolution characteristics of sandy desertification land in the area are also clarified. Result shows that in Pishan area,the areas of severe sandy desertification land and non-desertification land are all increasing,yet the increment of the former is greater than that of the latter and sandy desertification is still rapidly progressing.