Appearance of IRI in Iran opened a new course of political relations between Iran and Saudi Arabia. The occurrence being supported basically by Shiite revolutionary ideas caused considerable changes in the region. In this study, the impacts of IR on the relations between Iran and Saudi Arabia have been brought into consideration and analized. The elements affecting the relations may be counted as Iran`s intention for issuing IRI, Iran and Iraq war, Persian Gulf Cooperation Council, competition in OPEC, killing Iranian hujjaj and political activities of Shiites of Saudi Arabia. As shown in the paper, Saudi Arabia took the policy of reform and compatibility; yet, its politico-religious contradiction with Shiite government caused a permanent hostility to IRI.