Classifying theories of political trust into "cultural" and "institutional" is among methods of classification of such theories. In the cultural approach, any trust, including political trust, is deemed to be related to the process of socialization and culture of a society. At the micro level, the proponents of this approach argue that individuals who are raised to trust others will elicit more political trust. At the macro level, political trust is seen as an index of particular kinds of political culture. Institutional approaches, on the other hand, view political trust as an outcome of the way political institutions perform in a country (macro level) or people's perceptions of those institutions' performances (micro level). In the present paper which is based on a survey of a representative sample of students across all universities in Tehran, both cultural and institutional approaches are tested and their respective explanatory powers are evaluated. Specifically, the following two hypotheses, derived from cultural and institutional approaches, were tested:1. Individuals, who have learned through their socialization process to trust others more, are more likely to scores higher on a scale of political trust.2. The more positive a person's perception of performance of political institutions, the higher the level of political trust that he/she may show.Both hypotheses were confirmed in this study. However, the institutional explanation (the second hypothesis) revealed a stronger correlation (Pearson’s r=0.75 and Spearman's Rho=0.74) compared to the cultural hypothesis (r= 0.35 and Rho=0.30). It was also found that religiosity correlates positively with political trust in our sample of students.