The role of belief in Mahdism is based on Mahdavi culture, it has the ability to express views and provide strategic solutions in different human and social fields. The influence of this belief on the religious culture of the family manifests itself in all aspects of political-social and individual life, materially and spiritually. in fact, the Mahdavi family plays an irreplaceable role in the ideal and divine system, under the leadership of a perfect human being and the divine caliph for justice and wisdom to cover the whole world through the appearance of the Imam. The research methodology used in this essay is Library-based method with a descriptive-analytic approach based on historical and Hadith sources, focusing on the works of Ayatollah Ṣāfi Golpāyegāni. This research shows that the belief in Mahdism, materially and spiritually, has some effects on the religious culture of the families, which can gather the family members around its axis and integrate them and give them a single religious identity. In terms of the functions of believing in Mahdism, the following items make sense in the life style of those awaiting Mahdism: creating a suitable context for the future generation, educational and moral model, justice, fostering the spirit of hope, strengthening family relationship, naming children properly, giving charity, strengthening Mahdavi values in the education spaces.