Two elderly patients who had endoscopic sphincterotomy (EST) for their common duct stones developed acute cholangitis and, one of them also developed acute pancreatitis after the procedure. Despite the presence of an adequate sphincterotomy which allows subsequent spontaneous stone elimination, transient ductal obstruction during stone migration through the sectioned papilla is probably accountable for their complications. From the present reported experience, it is clear that expectant treatment of common duct stone after EST can be associated with definite hazards. Immediate biliary decompression with either active instrumental extraction or, when not feasible, insertion of nasobiliary catheter, should be performed to prevent these complications in selected patients.