Objective: The aim of present study was to determine the predictors of quality of marriage and also test the mediating role of subjective well-being in the relationship between four existential domains and quality of marriage. Methods: In terms of purpose, this study was an applied research and used structural equation modeling. The statistical population of research included all married people of Kermanshah city in 1400. The sample consisted of 441 married men and women who were selected by convenience random sampling method and questionnaires were completed by electronic survey method. Dehshiri Spiritual well-being Scale , Norton Quality of marriage Index and Warwick-Edinburgh subjective well-being Scale were used to collect data. SPSS and AMOS software version 26 were used to analyze the data and the data were analyzed using the structural equation model method. Results: The results of structural equation showed that relationship with self and relationship with nature have a significant relationship, both directly and indirectly, with the quality of marriage. subjective well-being has only directly and relationship with God only indirectly related to the quality of marriage, so that relationship with God through subjective well-being has a significant relationship with quality of marriage. Conclusion: The results of the research showed that a good relationship with God leads in good relationships with self and nature, and results of these good relationships strengthen people’s subjective well-being, and this in turn increases the quality of marriage. As we know, one of the dimensions of consultants' work is prevention. Therefore, it is recommended that counselors and psychologists provide the necessary training on establishing and enriching the four existential relationships to clients who seek premarital counseling or in individual counseling to clients. Counselors and psychotherapists in evaluating the problems of couples, as one of the variables affecting marital relationships, should also consider the extent of the four existential relationships and try to solve the problems of couples, to enrich these relationships.
