A 16-yr-old, female, captive-bred bontebok (Damaliscus pygargus) estimated to be 75 kg, was presented with a 1-mo history of chronic diarrhea and weight loss. A cause for the deteriorating condition was not found antemortem, and the bontebok was humanely euthanatized when it failed to respond to empirical therapy. On necropsy, numerous nodules were present on the pleural surfaces and within the lung parenchyma, the pancreas appeared inflamed and fibrotic. Histologic examination revealed lymphoma in the mesenteric lymph nodes, alimentary tract, reproductive tract, and liver. In the small and large intestine, rumen, esophagus, bile duct, and vagina, the neoplastic cells had a tropism for epithelium. The neoplastic cells within the epithelium and subepithelium of the alimentary tract stained positively for CD3, consistent with T cell differentiation.