Determination of serum amylase activity in 100 consecutive patients admitted to an alcohol detoxification unit revealed hyperamylasemia in 39 cases. Further clinical evaluation of 15 of the 39 alcoholic patients with hyperamylasemia was unremarkable except for bilateral enlargement of the parotid glands in two cases. Nine of the 15 patients demonstrated markedly low amylase to creatinine clearance ratio; however, macroamylase complexes were not detected in the sera of any patients. Serum isoamylase separation revealed that the mean salivary isoamylase for the 15 alcoholic patients was significantly (P<0.05) elevated as compared to the control values. Individually, the salivary-type isoamylase was clearly elevated in ten patients while pancreatic type isoamylase was elevated in four. These data indicate that elevated serum amylase activity occurs frequently in alcoholic patients. Hyperamylasemia in a large number of alcoholic patients is nonpancreatic in origin and may be related to the injurious effect of ethanol on salivary glands and other tissues.