Double gallbladder is one of the rare congenital anomalies of the gallbladder. Failure to detect an accessory gallbladder hampers diagnosis and treatment of cholecystitis, which might result in recurrent attacks of cholecystitis. In addition, presence of peritoneal folds extending from the stomach and duodenum to the gallbladder is very rare. Here we report the presence of a double gallbladder enclosed in a cystogastric fold of the peritoneum. During cadaveric dissection, we observed a cystogastric peritoneal fold that extended from the lesser curvature of the stomach and the first part of the duodenum to the gallbladder. The left end of the peritoneal fold merged with the lesser omentum. It enclosed two gallbladders: the main gallbladder and a small accessory gallbladder. The accessory gallbladder was a small pouch with its fundus attached to the main gallbladder by fibrous tissue, and its duct opened into the main cystic duct.