This case report describes colonic impaction with rodent hair and associated transcolonic membrane formation in a Savannah monitor (Varanus exanthematicus). Medical management with repeated warm soapy water enemas and oral laxatives was unsuccessful. Contrast radiographs and colonic endoscopy showed a complete membranous obstruction of the distal colon. Removal of the membrane was not possible endoscopically, therefore an exploratory celiotomy and a colotomy were performed to remove the membrane. Postoperatively, the animal was managed with ceftazidime, penicillin, and neomycin for antibiotic therapy, morphine and meloxicam for pain management, and lactulose as a laxative. The diet was changed to skinned adult mice once weekly, with neonatal mice containing oral medications force-fed daily. Twenty-four days after the surgery, the patient was reevaluated and was not passing feces. A second surgery revealed recurrence of the membrane and a dilated, atonic proximal colon; euthanasia was elected. In this case, we postulate that the colonic mucosa reacted to chronic irritation by forming a membrane around the hair bolus, which eventually led to a complete obstruction of the colonic lumen. This case highlights the potential problems intrinsic in feeding a haired rodent diet to varanid lizards and the role of contrast radiography and endoscopy in diagnosis of a transcolonic membrane.