Aim:This study aims to investigate the structural model of relationships between religious identity and social capital with the quality of life through the mediating role of self-differentiation among the students of Urmia University. Method:In order to do the research, from among the students of Urmia University (N:17568), 350 students were selected by the cluster random sampling method, and they answered the Khoshavi’s Religious Identity Questionnaire (2011), the Questionnaire of Christaan Grootaert et al. on Social Capital (2003), and the questionnaire for the Quality of Life of the World Health Organization (1989), and the Scale Scoring of Differentiation of Self Inventory (Skowron and Friedlander, 1998), which all of them have been localized. The path analysis method based on software LISREL (V. 8.8) and SPSS Amos was used to analyze the results.Finding: The findings showed that the model designed based on research data has a proper fitness, and there was a positive and significant relationship between direct paths, social capital, religious identity, and differentiation of self, with the quality of life. Furthermore, there was a positive and significant relationship between indirect paths, social capital, and religious identity, with the quality of life through differentiation of self.Conclusion:According to these findings, it can be concluded that differentiation of self, as a mediating factor, well regulates the relationship between social capital and religious identity with the quality of life.