Abstract: With the aid of the 3S technology， the land use change data during 1970s and 2005 in Mongolian Plateau were obtained. The spatial and temporal characteristics of the Mongolian Plateau land use change in the past 30 years was revealed by analyzing the changing process. The results showed that the total area of grassland was significantly reduced， a large area of bare land increased， urban and rural construction land expanded significantly， the area of cultivated land， forest land and water increased in Mongolian Plateau in recent 30 years. Grassland degradation and desertification became the significant spatial and temporal characteristics of landuse change in Mongolian Plateau， and the situation of Inner Mongolia was more serious than Mongolia. The forestry ecological engineering in Inner Mongolia played a positive role in protecting the ecological environment. Population， policy， economic and climate change were the main driving forces of the land use dynamic change in Mongolian Plateau．

Key words: land use, database, dynamics．