We studied 16 patients with Parkinson's disease (PD) with dysphagia and 8 young and 7 elderly normal controls videofluorographically to evaluate the nature of swallowing disorders in PD patients. In 13 patients, abnormal findings in the oral phase were residue on the tongue or residue in the anterior and lateral sulci, repeated pumping tongue motion, uncontrolled bolus or premature loss of liquid, and piecemeal deglutition. Thirteen patients showed abnormal findings in the pharyngeal phase, including vallecular residue after swallow, residue in pyriform sinuses, and delayed onset of laryngeal elevation. Ten of these patients also showed abnormal findings in both the oral and pharyngeal phases. Aspiration was seen in 9 patients. The oral transit duration was significantly longer in the patients with and without aspiration than in the control subjects. The stage transition duration, pharyngeal transit duration, duration of the upper esophageal sphincter (UES) opening, and total swallow duration were significantly longer in the patients with and without aspiration than in the young controls, but were not longer than in the elderly controls. These durational changes in the pharyngeal phase of swallowing were similar to those in the elderly controls. The findings suggest that the disturbed motility in the oral phase of swallowing may be due to bradykinesia. Although PD patients with dysphagia evince a variety of swallowing abnormalities, the duration of pharyngeal swallowing may remain within the age-related range until the symptoms worsen.