Objectives: When a married family member suffers from multiple sclerosis (MS), the collective physical and psychosocial well-being of the family is impacted and much of the burden is on the healthier spouse. The purpose of the present study was to determine the contribution of psychosocial support from spouses, friends, and others in overall family functioning in respect of Iranian patients with MS, considering the mediating role of spiritual experiences and moral foundations. Methods: Spouses of patients with MS were chosen through the judgmental sampling method. The research instruments comprised the Family Assessment Device, Social Support Appraisals Scale, Daily Spiritual Experience Scale, and Moral Foundations Questionnaire. Data analysis was done through the path analysis technique. Results: The subjects comprised 220 spouses of MS patients. We found a significant relationship between family support path and overall functioning mediated by the variable ‘spiritual experiences’, the root mean square error of approximation (RMSEA) value being < 0.001. Similarly, the relationship between spiritual experiences and moral foundations had a significant effect on overall family functioning (RMSEA < 0.001). After eliminating insignificant relationships and estimating fit indicators, the modified (adjusted) model indicated goodness of fit with data. Conclusions: This study found, for the first time in the Iranian community, a significant effect of family support focused on spouses of MS patients compared to the support from friends and others, with regard to family functioning. The mediating roles of spiritual experiences and moral foundations were confirmed. Further studies are suggested to delve into the role of family support for MS patients in developing countries.