Electoral systems play a decisive role in the quality of political representation and the level of political participation in elections. In Iran, elections have consistently served as one of the principal arenas of interaction between society and the political structure. This study employs library-based research and qualitative content analysis to examine the following question: What impact has the electoral system in Iran had on the level of political participation during the period from 2000 to 2022? The findings indicate that the Iranian electoral system, based on a majoritarian model and direct voting mechanisms, has on the one hand provided a foundation for political legitimacy and formal citizen participation, while on the other hand, through its structural and institutional characteristics, has influenced the scope and quality of such participation. Furthermore, the dominance of a candidate-centered logic, weak party institutionalization, the winner-takes-all nature of the electoral system, and the limitation of reforms to procedural aspects have reduced the system’s capacity to fully reflect social and political diversity in political participation. An examination of different electoral periods also reveals that participation reached very high levels in some elections, turning them into arenas of broad social mobilization, whereas in other periods a significant decline in participation was observed. This fluctuation suggests that political participation in Iran is influenced not only by the legal structure of elections but also by the level of political competition, public trust, and citizens’ perceptions of the effectiveness of their votes.