Pheochromocytomas are uncommon tumors of the adrenal medulla in canines that can be functional or non-functional. Functional tumors secrete catecholamines causing sporadic clinical signs due to sporadic hormone release. Non-functional tumors can cause clinical signs related to their space-occupying nature and invasion of regional vasculature and other structures. Pheochromocytomas are difficult to diagnose based on clinical signs and history alone. However, detection of an adrenal mass on abdominal ultrasound in correlation with clinical signs raises clinical suspicion in some cases. This case report will review canine pheochromocytoma along with its diagnosis, treatment, and prognosis.