Periampullary duodenal diverticula are associated with the presence of common bile duct stones, being encountered more frequently with the increase of age. We present the case of a 76 years old female patient, who underwents emergency surgery for a perforated lithiasic gangrenous acute cholecystitis and for whom we perform a cholecystectomy and an external biliary drainage using a transcystic tube. Both preoperative and postoperative imaging and endoscopic examinations certify the presence of a periampullary duodenal diverticulum. Postoperative cholangiography performed on the transcystic tube raises the suspicion of retained common bile duct lithiasis. An endoscopic retrograde cholangiopancreatography is performed, initially failing to cannulate the common bile duct. A precut sphincterotomy fistula technnique is performed, using as reference a guide inserted on the transcystic tube, with the extraction of biliay sludge from the common bile duct, and with subsequently favorable development. Association between common bile duct lithiasis and a periampullary duodenal diverticulum may represent a therapeutic challenge because of the increased risk of failure of the endoscopic treatment.