Abstract: The source region of the Changjiang River is situated in the center of the Qinghai-Xizang Plateau,belonging to typical periglacial environment.It is found that the region is the largest and highest plateau mire distribution area of plateau mire in the middle and low latitude zones of the world.Mire there covers an area of 8000km~2.The highest is 5350m above sea level.The mire in the pert-glacial region has special regional law.Strong thaw-freeze action is involved in mire formation process,so mire type peculiar to periglacial region is formed. Mire in this region is divided into 10 basic types such as periglacial strath mire. The formation mechanism,type characteristics and ecological features are discus-sed.Microlandforms are charaeterized by common grass mound cover,freezeswell raise,wide development of peat mire on peat accumulation,the feed of ice-meltwater and meltwater from frozen earth horizon,simple types of animal community and plant community,and many endemic species.In this region, there is only herb mire,lacking in moss Mire and woody mire.