Social cognition, including social perception, empathy and theory of mind, focuses on how people process, store, and apply information about other people and social situations, thus guiding social interactions. Specific patterns have been described in patients affected by different pathologies, such as Alzheimer's disease, autism and schizophrenia. Multiple sclerosis, an immune-mediated neurodegenerative disease, can affect global cognition in 40-70% of patients, with an impact on work and family status. Multiple sclerosis patients have shown a decrease in performance of tasks related to social cognition, and reflect changes in the structure and activity of specific brain areas. In the present review, we propose an operational definition of social cognition and its subdomains, and a comprehensive overview of how social perception, empathy and theory of mind are decreased in multiple sclerosis patients. Finally, we discuss its relationship with neuropsychiatric disorders, and expose some questions that remain unanswered.