This article studies and compares Islamic Republic of Iran and the United States of America leaders' discourses with using of Critical Discourse Analysis (CDA) as methodology. Particularly, we have analyzed the Speeches of Imam Khomeini and George W. Bush. The results show that Islamic Republic of Iran leader's discourse is pluralism, while the United States of America leader's discourse is conspiracy and monopolist. Dominant discursive order of media and leaders' speeches intend to form a positive image of their government legitimacy. We have analyzed the newspapers and governors’ discourses to discover their power relations to reproduce and to retain of the political and social structures that have legitimated their sovereignty. The government of the United States of America with using of power and violence language, and the government of Islamic Republic of Iran with using of authority language intend to form a positive image of their government legitimacy in international sphere.