Introduction: To investigate the effects of multiple sclerosis (MS) on male sexuality. Methods: While 61 men with MS were included into the study group, 60 healthy men constituted the control group in the study. In MS patients, such parameters as functional status and depression levels were assessed with the Expanded Disability Status Scala (EDSS) and the Beck Depression Scale (BDS), other parameters such as pain levels, sexual function and quality of life (QoL) were evaluated with the Visual Analog Scala (VAS), the International Index of Erectile Function (IIEF) and the short form-36 (SF-36), respectively. Results: Patients with MS were classified as 45 with EDSS <5.5 and 19 with EDSS >5.5. Mean VAS and BDI scores patients with MS were found statistically significantly higher, compared with those of the controls (p<0.05). Mean IIEF and all sub-group scores of SF-36 of patients with MS were found to be statistically significantly lower, compared with those of the control group (p<0.05). Mean EDSS in patients with MS was 2.75±2.42. While there was a positive correlation between IIEF scores of patients with MS, and mean mental and physical components of SF-36, a negative correlation was found between IIEF scores in MS patients, and age, disease duration, number of attacks, number of marital years and scores of EDSS, VAS and BDI (p<0.00). When BDI ≥17 was accepted as the threshold for depression, the depression was detected in 62.5% of patients with MS and 11.7% of the controls (p<0.001). Conclusion: Sexual functions are affected negatively in male patients with MS and seem to be associated with increased disability, pain and accompanying depression. Therefore, male patients with MS should also be evaluated with regard to sexual function, as well as disability during their follow-ups.