Purpose: Loneliness is one of the negative and unpleasant emotions that appear in couples for various reasons. Among the effective factors in the formation of loneliness are coping strategies and locus of control, which can have positive and negative effects. In addition, the mediation of social support plays a role in modulating loneliness. The research model was formed according to these relationships that were mentioned. Therefore, the purpose of the research was to predict the loneliness based on coping strategies and locus of control in couples with the mediation of social support.
Materials and Methods: This research was done by correlation method. The statistical population was composed of those couples who referred to the counseling center in district 4 of Tehran in 2020.  The sample size was determined by modeling method and it was 250 people. Data collection tools include: Russell's sense of loneliness (1978), Andler and Parker's coping strategies (1990), Rutter's locus of control (1996), Scott and Bruce's decision-making styles (1995), and Ziment et al.'s social support (1988). The data analysis methods were: Using the indicators of descriptive statistics, structural equations, path analysis, t-test and Sobel test, which was done by SPSS24 and PLS software.
Findings: The results of the research indicated that there was a direct relationship between each of the variables of coping strategies and the locus of control with the loneliness
Conclusion: Also, there has been a relationship between the feeling of loneliness and each of the variables of coping strategies and locus of control with the mediation of social support. The prediction of the loneliness has been fitted in the research model.