The aim of the study was to analyse swallowing function and to identify reliable prognostic factors associated with dysphagia in a consecutive series of patients with multiple sclerosis (MS). Swallowing examination was performed by means of indirect and direct methods (fiberendoscopic evaluation) in 143 consecutive patients with primary and secondary progressive MS. Dysphagia was found in 49 patients (34.3%). A close relationship with dysphagia was found in the patients with severe brainstem impairment (OR=3.24; 95% CI 1.44–7.31) as compared to the patients without. There was also a significant correlation with pronounced severity of illness (OR=2.99; CI 1.36–6.59). Compensatory strategies were sufficient to resolve the dysphagia in 46 cases (93.8%). The potential risk of aspiration and malnutrition and the high efficacy of swallowing rehabilitation suggests that all MS patients should have a careful evaluation of deglutition functionality, especially those with brainstem impairment and a high grade of disability level.