A left-sided gallbladder sinistroposition is a rare finding. These gallbladders are situated left of the falciform ligament and are located under the left lobe of the liver, between segments III and IV. Common bile duct duplication is also rare, and its cause is not yet fully understood. A 55-year-old woman presented to our hospital with symptoms of chronic cholecystitis. During the laparoscopic cholecystectomy, it was discovered that not only was her gallbladder to the left of the falciform ligament, but she also had a duplication of her common bile duct. Although cases of left-sided gallbladders have been reported in the past, and there has been a report of a sinistroposition of both gallbladder and common bile duct, we believe this is the first reported case of left-sided gallbladder sinistroposition with the complete duplication of the common bile duct. As we learn more about various anatomical anomalies of the gallbladder through the use of laparoscopic cholecystectomies, surgeons encountering a left-sided gallbladder should be aware of the potential for associated anomalies.