One of the most important topics in political sociology is how governments, when faced with the principle of "conflict of values and interests," choose policies and strategies, and how they respond to the demands, interests, aspirations, values, dreams, and feelings of identity and belonging of society. In Iran's case, intellectual and political elites, in response to how to manage the conflict of interests and values, sought to create legal institutions for managing conflicts and values following the Constitutional Revolution. During this period, political institutions such as laws, the parliament, political parties, and others were established to manage and control the diverse conflicts of interests and values. However, this research argues that not only did institutional policies, particularly the National Assembly, fail to provide a balanced, equitable, and institutional response to these conflicts and disputes, but the National Assembly itself became functionally contradictory and contributed to intensifying, producing, and reproducing disputes and the return of despotism. In this regard, the present research aims to examine, describe, and analyze the functional conflict of the National Assembly, exploring why it failed to contribute to the creation and reproduction of democratic political stability and instead became a source of political instability or an authoritarian and autocratic political order. The research hypothesis is based on the premise that the National Assembly, influenced by variables such as institutional overlap, institutional weakness, institutional transformation, institutional influence, and conflicts of interest, experienced functional conflict and thus lost its effectiveness, changing from a powerful political institution into a political tool for the reproduction of authoritarianism. This research uses a qualitative methodology (historical sociology) and a new institutional approach, collecting data through library and archival methods. Data analysis is conducted using a theoretical framework, institutional theory, and the concept of institutional functional conflict at the political level.