Abstract: It’s a conclusion acknowledged very early by the academic circles that the national culture is endowed to have an ability to adapt actively in its environment.However,the former research was unfolded mainly on the ecological adaption of culture.The fact we are now facing is:ecological crisis frequently appears everywhere in the world,that’s the reason why culture lost its function in the ecological adaption.The author thinks that the cultural adaption has double identity,which not only has to adapt its ecological environment,but also its social background.The predecessors cared very less about the social adaption of culture,so  this is just the reason why we can’t explain the frequent happenings of present ecological crisis.Therefore,this paper takes recent five-hundred-year cultural change of Miao,Dong and Yi which are three minority groups in the south-western part of our country,through the analysis of culture and politics,reveals how the local knowledge of three nationalities became distorted and lost under the unified national policy adopted by central imperial court,clarifies the rules of cultural social adaption,helps to find the countermeasures for recovering and utilizing these local knowledge.

Key words: local knowledge, ecological adaption, social adaption