The purpose of this study was to "investigate the relationship between mental health, sexual self-concept and the role of patterns of communication with instability in marriage." The method of this research was correlation. The statistical population of this study was couples referring to counseling and family counseling centers in Tehran. To this end, 260 people were selected as available. The instruments used in this study included Edwards Marriage Instability Questionnaire, Christensen & Salavian Communication Patterns (CPQ), Goldenberg Mental Health (GHQ), and Snell's Sexual Self-Concept (MSSCQ). Structural equation modeling (factor analysis and path analysis) was used to analyze the data using AMOS18 and SPSS22 software. According to research findings, mental health, sexual self-concept and intermediary role of communication patterns predict the instability of marriage. Mental health indirectly through constructive communication pattern is a significant predictor of instability in marriage. Among its components, anxiety and insomnia have a positive and significant correlation with the criterion variable. As well as expected / discarded and avoidable patterns (inefficient) have a positive and significant correlation, and the constructive coupling pattern has had a negative correlation with the instability of marriage. The gender variable through the total path coefficient can predict the instability of marriage and its components are negatively correlated with the instability of marriage.