Prolonged esophageal scintigraphic transit time is frequent in diabetic patients and is related to autonomic neuropathy. In this study, esophageal scintigraphic transit time was correlated to esophageal motor function as evaluated by video-radiography and manometry in 13 diabetic patients. An abnormal scintigraphic transit time (greater than 15 s) occurred in 6 patients. All patients with abnormal transit time showed abnormal results at video-radiography (n = 4) and/or manometry (n = 5), which were observed in only 2 of 7 patients with normal transit time (both with abnormal video-radiography and manometry). A prolonged scintigraphic transit appears reliable as an indicator of disturbed esophageal smooth muscle function since it is well correlated with abnormalities shown by a combination of video-radiography and manometry.