This study investigates the political relationship between Iran and Pakistan after the Islamic revolution. The method used in this research is descriptive and analytic, and the documentary approach was used for data collection. The main question of the research is what problems have influenced the political relationships between Iran and Pakistan after the Islamic revolution? The main hypothesis of the research presents that the Islamic revolution and the Soviet occupation of Afghanistan had a negative impact on Iran and Pakistan relationships. The study findings show that the sectarian prejudices and the sectarian wars are the characteristics of Pakistan that has influenced the relationships between Iran and Pakistan. Before the Islamic revolution, sectarianism and the Sunni-Shai issue did not have any decisive role in the relations between the two sides. In the development process of relations between Iran and Pakistan, Afghanistan is present as an important security variable. Iran is a strategic partner for Pakistan.This study investigates the political relationship between Iran and Pakistan after the Islamic revolution. The method used in this research is descriptive and analytic, and the documentary approach was used for data collection. The main question of the research is what problems have influenced the political relationships between Iran and Pakistan after the Islamic revolution? The main hypothesis of the research presents that the Islamic revolution and the Soviet occupation of Afghanistan had a negative impact on Iran and Pakistan relationships. The study findings show that the sectarian prejudices and the sectarian wars are the characteristics of Pakistan that has influenced the relationships between Iran and Pakistan. Before the Islamic revolution, sectarianism and the Sunni-Shai issue did not have any decisive role in the relations between the two sides. In the development process of relations between Iran and Pakistan, Afghanistan is present as an important security variable. Iran is a strategic partner for Pakistan.Keywords: foreign relations; ethnicity; religiosity; geographical genome.