The Islamic revolution of Iran is the biggest revolution and social evolution of the Muslim world in the contemporary world. There have been many theories and analyzing approaches applied for explaining the manner and reason of the occurrence of this revolution. However, the crisis theory of Jü rgen Habermas is an approach which besides its efficiency and expressiveness has not been considered so much. From Habermas’ viewpoint, in the relations among the three economic, political and socio-cultural domains, the four economic, rational, legitimation, and motivation crises can be recognized. The appearance of these crises in a structure, especially the current framework of capitalism, can be a sign of its weakness and destroying. This writing tries to explain the manner of the Pahlavi’ s overthrow and the rise of the Islamic revolution through this theory. From the writer's view, Pahlavi's semi-capitalist regime had a general inefficiency in different aspects of its structure and all the four crises mentioned by Habermas, especially the legitimacy crisis (trans-material and applicable) are seen in it. On the other hand, the discourse of the Islamic revolution in Imam Khomeini’ s reading, and its other-making and antagonistic relation with Pahlavi’ s discourse, could articulate a system of significations and concepts through showing the highest level of availability and credibility. This covers the malfunctions and crises of Pahlavi’ s regime and reaches the position of a hegemon discourse.