Based on the spatial dataset obtained from the TM remote sensing data in 1986,2000 and 2014,combined with the field investigation data,the maps of the land cover pattern in the source of Yangtze River were made,and the transition probability between all kinds of land cover was determined by using the amplitude of the land cover pattern changes during the three different periods. In addition,Markov model of land cover change in this region was established and vali-dated by the transition probability. The characteristics and tendency of land cover changes were analyzed and forecasted with the Markov model. The results indicated that the characteristics of land cover change were coincided to Markov process,thus,the Markov model could be used to validly simulate the process of land cover change in the source region of Yangtze River. The degradation trend of land cover in the source region of Yangtze River was extremely evident. The areas of wetland and alpine grassland with high-mid coverage continued to decline,while the area of low cover alpine grassland and bare land had consistently been increasing. However,with the establishment of the Three Rivers Headwaters Nature Reserve and the increase of precipitation in this region since 2000,the degradation trend of vegetation has been relieved obviously.