We investigated swallowing function of 29 patients with multiple system atrophy (MSA) by videofluoroscopy and manometry. Abnormal findings in videofluoroscopy were generally consistent with those in Parkinson's disease. Although findings of videofluoroscopy were not correlated with a history of aspiration pneumonia, severity of disease was significantly correlated with a history of aspiration pneumonia. Oropharyngeal and hypopharyngeal swallowing pressures of the patients were decreased to 73.9 ± 48.4 mm Hg and 85.3 ± 42.9 mm Hg, respectively, both of which were significantly different from the pressures of the control group. Incomplete relaxation of the upper esophageal sphincter was seen in 23.1% of the MSA patients, all of whom had had MSA for more than 5 years. In conclusion, patients with MSA are at risk for aspiration pneumonia as disease severity increases, and the swallowing function of patients with more than 5 years' duration of MSA should be routinely followed up with both videofluoroscopy and manometry.