Abstract.A 23-year-old female patient with malignant pheochromocytoma was admitted to the Tokyo Women's Medical University. The patient had been clinically diagnosed with Holt-Oram syndrome at birth. Since she had complex congenital heart disease, chronic heart failure, and severe hypoxia, the risk surrounding surgery to remove the primary tumor was predicted to be very high, and subsequently, chemotherapy was performed. The patient was not able to continue chemotherapy due to adverse effects. However, for one year, both her hypertension and catecholaminedependent symptoms were well controlled by an alpha-adrenergic and beta-adrenergic receptor blockade, although the patient did experience high plasma norepinephrine levels. To our knowledge, this is the first report of a patient with the combination of malignant pheochromocytoma and Holt-Oram syndrome. A correlation between chronic hypoxia and pheochromocytoma has been reported. This instructive case reminds us to consider the possibility of pheochromocytoma with congenital heart disease when these types of unexpected or unusual symptoms are encountered.