Abstract: The special habitats for endangered species, Adenophora lobophylla Hong population to grow and develop are formed in the northwest of Sichuan province and influenced comprehensively by the many factors such as external disturbance, geology, topography, climate, soils, biology.The external environmental factors which is leading the A.lobophylla population to be endangered status are: habitat was destroyed by overcutting of forest, bringing barren hills under cultivation; grazing; and diging it up as Chinese medicine; the geological disaster such as earthquake, landslip, mud-rock flow occuring frequently; Climate disaster such as the flood, the spring and summer drought; the harm of rust, pest underground and wildlife etc.All of these factors endanger the population number and the growth of individual periodically, frequently and extensively.Any action to damage the locative habitat from humane being should be stopped immidiately; the conservancy area for the A.lobophylla to be conserved at province level has been suggested to be set up in Jinchuan county; The introductive, cultivation of A.lobophylla population in the proper region should be carried out; and the research work should be continued in order to get the general regulation of the endangered species.

Key words: Engangered plant species, Adenophora lobophylla, External endangered factors, Northwest of Sichuan