Researchers, political parties and groups, and states have always been interested to understand the behavior and mental processes influencing the political choice, the reasons underlying participation or non-participation, and the behavior and motivation of voters. In addition to the contextual factors (e.g., mass media, groups, political parties, states, ideologies, ethnicity, religions, regions, social classes, and the like), the behavioral processes of feeling, perception, motivation, or emotion can also play a determining role in the political attitude, understanding, and choice—alongside the prevailing conditions, culture, and atmosphere of a given society. This is a legitimate research topic in the field of political psychology worthy of further investigation. In this respect, the present research intends to examine emotion as one of the internal, behavioral states and processes influencing the political choice and the participation level.The motivation behind voters’ participation in elections depends on various factors. The first and perhaps the most important one is the acceptance of sovereignty and state by people, so the legitimacy of the governance system, trust in the health and fairness of elections, and confidence about the candidacy of real representatives of people are the determining factors influencing people’s participation. The second important factor is the general atmosphere prevailing in society, that is, the extent to which the most important issues of the day can motivate and encourage people’s participation in elections. Economic, social, and political crises or the events such as the possibility of war and internal disputes, together with healing and savior-like promises, can be considered as effective issues in the election process. Definitely influencing the participation level, the third significant factor is the candidacy of prominent, popular, charismatic, and influential figures. Moreover, a competitive and partisan atmosphere can increase the participation level to its high. Finally, by helping individuals, parties, and candidates in different ways, advertising and media performs a significant role in their victory or defeat. Besides these important reasons, the findings of political psychology show that in many cases the election result usually depends on emotion as a factor influencing the type and level of people’s participation in elections.Offering a brief overview of the Iranian presidential elections, the present research employs the theory of rational choice as a theoretical framework and the descriptive–analytical method in order to analyze the collected historical documents. The research tries to answer the key question of whether people’s tendency in elections is more influenced by rational choice or by emotion. In other words, which variable has a more influential role in the election process? and what spectrum of society, why, and under what conditions is affected by the emotional atmosphere? Assuming the rational choice as a logical goal, regardless of the positive and negative effects of emotion on the choice, an overview of the Iranian presidential elections confirms the hypothesis that influential events along with the presence of certain figures and competitors at different times can arouse emotion and create a passionate political and competitive atmosphere, leading to a high participation level.The study briefly reviews the results of the Iranian presidential elections from the beginning until now, but it especially focuses on the phases that witnessed the highest and lowest participation rates. The highest rate was seen in the third election (the election of Ayatollah Khamenei), the seventh election (the election of Mohammad Khatami) and the tenth election (the election of Mahmoud Ahmadinejad) while the sixth election (the election of Hashemi-Rafsanjani) and the thirteenth election (the election of Ebrahim Raisi) had the lowest level of people’s participation.There are various reasons behind the decrease and increase in the participation rate. The focus on motivational factors makes manifest the undeniable effect of changes in political emotion on the participation level. As an answer to the research questions, the findings generally confirm the theory of rational choice subscribing to the view that people naturally rely on rational calculations and consider personal interests in each choice, including the political one. However, the study of the presidential elections in Iran made clear that, in addition to motivational factors, other factors such as certain events and the presence of certain political figures at different times could arouse emotion and create a passionate political and competitive atmosphere, leading to an increase in the participation level.