In order to accurately grasp the distribution of degraded forest land in the Three-North Shelterbelt Project area of Inner Mongolia,promote the construction of the Three-North Shelterbelt Project,and continuously improve the quality of forest resources and the ecological environment in the Three-North Shelterbelt Project area of Inner Mongolia,Forestry and Grassland Bureau of Inner Mongolia Autonomous Region organized the survey of degraded forest land in the Three-North Shelterbelt Project area in 2021. The results showed that the area of degraded forest in the Three-North Project area was 3019432.30 hectares,of which 16.86% and 83.14% were degraded forest and degraded shrub land. The main reasons for forest degradation were physiology,site,disaster and human activities. The area of forest degradation caused by physiology and disaster accounted for 45.81% and 38.13% respectively. Mildly degraded,moderately degraded,and severely degraded areas accounted for 0.88%,64.86% and34.26 %,respectively. The degraded forests were mainly distributed in the western part of Inner Mongolia,and further measures such as renewal,restoration,tending,enclosure and habitat restoration should be taken to restore the degraded forests so as to maintain the achievements of regional ecological construction.