Background: Multiple sclerosis is a chronic neurological disease that may cause swallowing disorders. Dysphagia is a common problem, which patients with different levels of disability may encounter, but it is usually underestimated; therefore, effective assessments need to be performed before any serious complications. The aim of this study was to identify the frequency and characteristics of dysphagia in multiple sclerosis patients of Khuzestan MS society, using a Persian version of Dysphagia in Multiple Sclerosis (DYMUS) questionnaire. Method: 105 consecutive MS patients (84 F and 21 M, mean age 33.8 +/- 8.5 years, mean disease duration 3.5 +/- 3.1 years, mean Expanded Disability Status Scale (EDSS) 1.8 +/- 1.3) participated in the study and the DYMUS questionnaire was administered by a trained speech therapist. Results: The results have shown that 55 MS patients (52.4%) had dysphagia and the dysphagia was significantly associated with the disease course of MS (p = 0.02). However, significant associations between DYMUS values and EDSS, disease duration, age, and gender were not observed. (Respectively, p = 0.4, p = 0.09, p = 0.1, p = 1.0). In the dysphagia group, based on dysphagia severity, 17.1% and 35.2% of patients had mild and alarming dysphagia, respectively. Although, the patients with alarming dysphagia had longer disease duration, higher EDSS score and more with SP, PP and PR disease course than the patients with mild dysphagia, these differences were not significant. Conclusion: The oropharyngeal dysphagia in MS patients is very common even in early stages of the disease; therefore, it is important to assess these patients carefully and to initiate a treatment program if needed.