Abstract: Regional land use dynamic monitoring analysis is an important part of land use study. It provides basis for rational use of regional land and government’s macro-control. In this study, Minqin County in Gansu province of China was adopted as the study area. Based on the two Landsat TM image sets in 1991 and 2009, the land use changes of Minqin in 18 years were monitored and analyzed dynamically by the computer automatic interpretation and visual interpretation method. According to the land-use map, the transition matrix was used to study the changes of different kinds of land use types in Minqin. The results show that the desert area in Minqin has increased by 643.67 km2, including 541.35 km2 saline soil and 233.12 km2 vegetation area. It indicates that the vegetation has been severely damaged. The vegetation area has decreased by 441.87 km2, most of which was transformed to deserts and saline soil. In this study, the Markov model was applied to predict the land use trends of Minqin in next decades. It pointed out that the desert area would increase by 0.17% each year, the vegetation area would be deteriorated before getting better and the city subdivision would be increased by 0.028% each year. This study provides scientific basis for the eco-environmental control of Arid and Semiarid Region.