The purpose of this study was to examine the contribution of demographic, medical, and social support variables in predicting the mental health dimension of quality of life (MHD/QOL) among people with multiple sclerosis (MS). Eighty-two participants of employment age recruited from hospital neurology clinics specializing in MS completed a demographic questionnaire, and 69 completed the Multiple Sclerosis Quality of Life Inventory (MSQLI). In addition, a neurologist used the Expanded Disability Status Scale (EDSS) to assess the medical status of each participant.The number of young children in the family, MS duration, cognitive impairment, and social support were predictors of MHD/QOL. Employment was not associated with MHD/QOL score. Social support made a significant and unique contribution to the MHD/QOL beyond all the other variables. Implications for social work practice are presented.