Bakhtiari clan is one of the important and powerful tribes of South-western Iran during its history experienced several vicissitudes. It also has played a really effective role in political developments of modern Iran. The socio-political structure of Bakhtiari’s tribal power has been subjected to a special pattern which experienced certain changes during its history. Despite the other tribes, power structure of Bakhtiaris constituted of a hierarchical structure including different levels and ranks. At the other hand, the kinship structure of Bakhtiari clan, which included the smallest unity i.e. family (Behan: black tent) to the largest one, i.e. the ling (branch) seems to be the main cause of its centrifugal nature. In conditions which these semi-independent parts combined and integrated into a united structure, formation of a tribal confederation or union was the result. In former times, the Khan’s social statute was at the highest level of tribal authority and magistrates, headmen, and deans stand next to them respectively. But the gradual rise of the modern state, consolidation of its central power and the expansion of military forces resulted in a dwindling of Khan’s power. This, in turn caused the political structure of Bakhtiaries, especially the status of the Khan, to encounter with some essential changes; in next periods there was no more the traditional status of khan at the top of this tribal structure. How we can describe the socio-political structure of power in Bakhtiari society and its constitutive nature, what were the main changes it endured during recent centuries and what were the causes behind these changes are questions which this study aims to answer. To attain this purpose it tries to develop a research within an analytical/descriptive method. Its main source is a volume of data gleaned from library references which are organized, evaluated, and analyzed to attain the purpose.