The study of potential vegetation can reveal the impacts of climate on vegetation. It is the starting point for studying vegetation-environmental classification and relationships,and the key point for studying global change and terrestrial ecosystems. It has guiding significance for the restoration and reconstruction of regional vegetation. Using the comprehensive sequential classification system (CSCS),we carried out a GIS simulation study on the spatial distribution of potential vegetation in China in the past 30 years (1986-2015) and the future three periods (2030s, 2050s and 2080s) under the RCP4.5 scenarios issued by IPCC5,and analyzed its sensibility to climate change. The results showed that: (1) Differences existed in the number of potential vegetation classes and the proportion of each class in different periods. The tropical-extrarid tropical desert (VIIA) was commonly absent in all periods. (2) With respect to the distribution area of potential vegetation,the area of cold-dry potential vegetation decreased whereas that of warmhumid potential vegetation increased,with extension,reduction and fluctuation being the three typical variation patterns. Moreover,the gravity centers of potential vegetation categories moved in different directions and at different distance. (3) The sensitivity of potential vegetation to climate change differed,with different sensitivity regions showing an interphase distribution. The distribution areas of regions with the highest,higher,and lower sensitivity accounted for 2.28%, 14.39% and 43.82% of the total national area,respectively.