The aim of our study was to evaluate postprandial emptying of the gallbladder and common bile duct (CBD) in 20 patients with gallstones and in 20 diabetic patients with or without autonomic neuropathy. Gallbladder fasting volume was significantly increased in patients with multiple stones. Diabetics with autonomic neuropathy showed a decreased gallbladder emptying rate. CBD size did not show any significant change in all groups examined.