A 14-year-old male domestic short-haired cat was examined because of anorexia, depression and intermittent vomiting. Blood chemical analyses indicated the presence of liver disease and radio-opaque masses were seen in the region of the gall bladder on plain radiographs of the abdomen. Cholecystography was unsuccessful. Cholecystotomy was performed and choleliths removed from the gall bladder and the obstructed common bile duct.Escherichia coliwas cultured from the bile; thus ampicillin was administered post-operatively. The choleliths were composed mainly of bilirubin and calcium, and a bacterial cause for their formation is suggested. The cat recovered and was normal 9 months after surgery.