Mirizzi's syndrome accounts for an important risk for bile tree injury during surgery, since preoperative diagnosis is missed in half of the cases and is often difficult to differentiate from carcinoma. A 79-year-old male, with a known history of cholelithiasis, was admitted with a progressive obstructive jaundice over 20 days, without pain, fever, or other symptoms. Magnetic resonance cholangiopancreatography described possible microlithiasis of the distal bile duct, but on endoscopic retrograde cholangiopancreatography (ERCP), an irregular stenosis was detected under the junction of hepatic ducts, which was described as possibly neoplastic. A temporary stent was placed and the patient was referred for surgery. On first view the gallbladder appeared hard, embedded in adhesions, giving the impression of an unresectable tumor and the bile duct was not approachable. After a fundus-down incision of the gallbladder multiple stones were extracted. Frozen biopsies from the gallbladder wall were negative. The incision was extended towards the gallbladder neck and a large communication with the common bile duct (CBD) was revealed. A difficult partial cholecystectomy was performed, followed by cholecystojejunostomy with a Roux-en-Y jejunal loop. The patient had a totally uneventful postoperative course. Stent removal was succeeded endoscopically 1 month later. The importance of preoperative ERCP and CBD stenting is highlighted in this article. ERCP may have failed to distinguish Mirizzi's syndrome from carcinoma, however the stent placement saved the cardiologically compromised patient from further surgical manipulations. Therefore, in ambiguous cases, whatever the final diagnosis turns to be, either carcinoma or Mirizzi's syndrome, CBD stenting can be useful for the final management of the patient.