Between the time of the victory of the revolution and the final adoption of the constitution of the Islamic Republic (February 22, 1359 - December 11, 1358), various political trends around the shape and nature of the post-revolutionary political system of Iran and its relation to party democracy and politics were raised; Imam Khomeini, the leader of the revolution and the new Islamic Republic's system, spoke about his political and intellectual views on the issue of the form and content of the Islamic Republic's rule and the constitution that emerged from it. The purpose of the present research is to explain the relation between the republicanism and the system of Islamism in the government of the Islamic Republic; hence, to analyze the position of pluralism and party politics within the framework of the Islamic republic's rule of Imam Khomeini. The type of research is descriptive-analytic, and the method of research is a historical survey using the "process tracking" pattern. Findings of the research show that Imam Khomeini guaranteed the republicanism of the regime in the way and the rule of law in the content between the victory of the revolution and the adoption of the constitution of the Islamic Republic of Iran. Also, in his political views, pluralism and party politics were confirmed in the framework of the foundations of the government of the Islamic Republic and the interests of the country