Pheochromocytoma is a rare disease. A retrospective study of the signs and clinical course of this disorder was performed by evaluating medical records. Our fidings indicate that the prevalence of pheochromocytoma was equal in men and women, and most patients (56%) were in their second and third decades of life. In 10% of the cases, the disease was bilateral, and in 13% it was outside the adrenal (totally para-aortic). The tumor was more common on the right side (8%), and 3.5% were familial. Almost all cases had a history of hypertension and hypertensive crises. Attack-like episodes of clinical symptoms and signs and hypertension were observed in 98%, headache in 71% and profuse perspiration in 68% of the cases. An abdominal mass was palapated in 13% of the cases, 26% had overt diabetes, 23% had ECG changes. Malignancy was observed in 4%, with metastases to the liver (n=2) lung (n=1) and spine (n=1). In the latter four cases, the metastic lesion was histologically proven to be pheochromocytoma. In three of the 28 female cases, the first hypertensive crisis occurred during pregnancy causing abortion in one case.