In this paper, the declarations of the Union of Islamic Iran People Party (Participation Front) and the political group of the Association of Combatant Clerics from the reformist spectrum were investigated considering the collective protest actions that took place in 1999, 2009, 2019, and 2022. In order to implement this research, the statements issued regarding collective protest actions by the Union of Islamic Iran People Party and the political group of the Association of Combatant Clerics were referred to. To collect data, their statements were reviewed and the obtained data were analyzed through thematic analysis method, which is one of the qualitative research methods (descriptive and exploratory). This research seeks to answer this main question: What has been the evolution of the devlares of the Union of Islamic Iran People Party and the political group of the Association of Combatant Clerics regarding the collective protest actions that took place in 1999, 2009, 2019, and 2022? Also, this research seeks to answer these sub-questions that what the declarations of the Union of Islamic Iran People Party and the political group of the Association of Combatant Clerics were regarding the four collective protest actions, and what the similarities and differences between these declarations are. This research reached the following results: 1. The declarations of the clerics’ assembly regarding the events after the elections of 2008 and the events of 2022 have changed compared to its declarations in the events of 2019, but that of the Union of Islamic Iran People Party has not changed regarding the aforementioned protest actions. The Union of Islamic Iran People Party and the assembly of militant clergy have always emphasized democracy, referendum and freedom of expression and criticized the way of governing and the functioning of the conservative faction. 2. The declarations of the Union of Islamic Iran People Party and the political group of the Association of Combatant Clerics have little difference and they have many similar declarations.