This research aims to provide a comprehensive critical analysis of the historical trajectory and structure of the Islamic Republic of Iran’s immigration policy process concerning Afghan migrants following the Islamic Revolution. The central issue is that despite over four decades of extensive Afghan presence in Iran, the policies adopted in this regard have lacked coherence and a sustainable approach, often being subservient to the prevailing political, security, and economic conditions of the time. The research methodology is qualitative and documentary analysis, with data gathered through the examination of laws, governmental resolutions, official documents, and national and international reports. The theoretical framework is based on the Public Policy Process Theory and the approach of social justice. The results indicate that Iran’s immigration policies towards Afghan nationals have, in most periods, been temporary, reactive, and unsystematic, rarely based on assessments of social and economic impacts. The continuation of a security-oriented perspective and the lack of a citizenship approach have prevented the formation of sustainable migration policies. Finally, it is recommended that a revision of existing policies be undertaken, emphasizing the principles of social justice, institutional coherence, and the participation of domestic and international stakeholders.