BACKGROUND: Pheochromocytomas are relatively uncommon neuroendocrine tumors arising from the adrenal medulla. They sporadically produce and secrete catecholamines, resulting in fluctuating hypertension and tachycardia. Clinical signs are vague and often non-apparent, and pheochromocytomas are generally diagnosed incidentally in patients that are presented for some other concurrent disease process. Successful treatment requires adrenalectomy, and prognosis is good for patients that survive the surgery and immediate post-operative period, when serious complications are most likely to occur. CASE: This case report describes the diagnosis and successful treatment of a 7 year old female spayed dachshund with a splenic hematoma and a pheochromocytoma. The patient was presented to the Cornell University Hospital for Animals (CUHA) Emergency Service for evaluation of a distended and firm abdomen that was first noted three weeks prior. Diagnostics revealed a large, cavitated intraabdominal mass of presumptive splenic origin as well as a right adrenal mass. Splenectomy was performed successfully and without complication, however adrenalectomy was met with drastic intraoperative fluctuations in heart rate and blood pressure that proved difficult to manage. Despite complications, the adrenalectomy was completed and the patient recovered from anesthesia uneventfully. The patient continues to do well at home three months postoperatively. CONCLUSION: This report reviews the preoperative, intraoperative, and postoperative management for pheochromocytomas in dogs.