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Neoplasia in nondomestic bovids is rarely reported in the literature, leaving prevalence largely unknown. A retrospective review of the pathology records of 101 scimitar-horned oryxes (Oryx dammah; SHO) housed at a single zoological institution over more than 50 years identified six cases of pheochromocytoma. All six cases were geriatric individuals ranging from 15 to 22 years of age. Five cases presented with benign pheochromocytomas, and one case presented with both a malignant and benign pheochromocytoma. Histological features of malignancy for this case included diffuse infiltrative growth, vascular and capsular invasion, tumor necrosis, increased mitotic activity, cellular pleomorphism, and distant metastasis to the liver, diaphragmatic skeletal muscle, and cranial peritoneal cavity. While the malignant tumor exhibited invasive features which may have contributed to morbidity and mortality, none of the six cases exhibited clinical signs or postmortem findings typically associated with catecholamine excess. As such, these pheochromocytomas appear to have been nonsecretory, as is generally observed in domestic bovine cases, wherein pheochromocytomas are typically incidentally identified at slaughter. Nevertheless, the malignant case in which widespread metastasis occurred indicates that pheochromocytoma is an important differential to consider for general decline or a mid-abdominal mass in this species. More broadly, the scarcity of published neoplastic data on SHO highlights the need for collaborative, multi-institutional data sharing to establish broader epidemiological trends in managed populations.