Social support is a protective factor against cognitive decline in the general population. However, the relationship between social support and cognitive functioning among persons with multiple sclerosis (MS) is not well understood. The present study aimed to investigate the associations between different aspects of social support and cognitive performance among persons with MS. A volunteer sample of 60 persons with MS completed the Medical Outcomes Study Support Social Survey 5-item short form (MSSS-5) and the Social Network Index (SNI). Cognitive functioning was assessed through a virtually-administered neuropsychological battery. Multiple linear regressions were conducted to examine the associations between social support measures and cognitive performance. In models adjusting for level of premorbid functioning, both perceived social support (i.e., to what extent one receives assistance from their social network; p=.002) and total size of social network (i.e., total number of people one regularly talks to; p=.002) were significant predictors of processing speed/executive functioning with moderate effect sizes. However, when we accounted for employment status in a post hoc analysis, the association between social network size and processing speed/executive functioning became statistically insignificant, while the relationship between perceived social support and processing speed/executive functioning remained significant (p = .002). Greater perceived social support is associated with better performance on processing speed/executive functioning measures among persons with MS, independent of effects from premorbid functioning and employment status. Maintaining a strong social support network may be an important factor in optimizing cognitive health in MS.