Political culture represents a society`s widely held, traditional values and its fundamental practices; foreign policy decision makers tend to make policies that are compatible with their society`s political culture because they share, if not all, many of those values. Among the various factors influencing Iran`s foreign policy, the role of political culture seems to be rather underestimated. This article seeks to analyze the role of Iran`s political culture in shaping the country’s foreign policy, through a comparative study of the hardline foreign policy of former president Mahmoud Ahmadinejad and the moderate foreign policy of current president Hasan Rouhani. Accordingly, this paper`s main question is the following: What is the role of political culture in the change in Iran`s foreign policy during Ahmadinejad and Rouhani’s presidencies? Our main hypothesis is that the oscillation of Iran`s foreign policy between aggressiveness and moderation reflects Iran`s two simultaneous contradictory political cultures. In this theoretical-analytical paper, we apply a descriptive-explanatory method to examine our hypothesis. First, we will have a very short discussion of the various factors shaping Iran`s foreign policy. In the second section, we will shed light on the main elements of Iran`s political culture, which seem to influence the country’s foreign policy. The third section of this article will compare Iran’s foreign policy during President Ahmadinejad and President Rouhani; we will try to demonstrate how Iranian leaders who are stuck in Iran`s contradictory political cultures, have reacted and why. Finally, the impact of Iran`s political culture on its foreign policy change will be analyzed.