The spontaneous rupture of a pheochromocytoma is rare and can be potentially fatal. We report a case of a tumor size reduction of a ruptured pheochromocytoma after transcatheter arterial embolization (TAE). A 60-year-old Japanese woman was referred to the emergency department of another hospital with a sudden onset of left lateral pain. Computed tomography of the abdomen revealed adrenal hemorrhage with a 5.7 cm adrenal mass, and she was transferred to our hospital for treatment. Considering that she had marked hypertension (193/115 mmHg), we made a provisional diagnosis of left lateral pain due to a ruptured pheochromocytoma. She underwent TAE, and the hemorrhage was successfully controlled. She was started on oral doxazosin for hypertension. The dose of doxazosin was increased to the extent that orthostatic hypotension did not develop, and blood pressure was well controlled. After discharge, the tumor size gradually decreased to approximately 1.0 cm within six months. Six months after TAE, elective laparoscopic surgery was performed, and the diagnosis was confirmed by histopathology. We observed a decrease in the size of the ruptured pheochromocytoma after TAE. To reduce the risk of laparoscopic adrenal surgery, it may be useful to monitor the size of a ruptured pheochromocytoma after TAE before deciding the surgery time.