Pheochromocytomas and functioning paragangliomas are rare tumors arising from the primitive neural crest. Approximately 10% of adrenal pheochromocytomas are malignant. Malignant pheochromocytomas usually recur in the retroperitoneum or appear as metastatic deposits in bone, lung, or liver. Here, we report a 51-year-old woman with malignant pheochromocytoma with a peritoneal metastasis, which is a very unusual metastatic site. She was referred to the hospital with headache, abdominal pain, and ileus. A right adrenal mass was surgically removed in May 1997. Pathologic examination revealed pheochromocytoma and capsular with adjacent muscle invasion. During the next 3 years, the patient remained well. The disease recurred in 2001, with hypertensive episodes and peritonitis carcinomatosa. Further investigation revealed no other metastatic sites. Peritoneal metastasis is very rare in malignant pheochromocytoma and generally is attributed to direct peritoneal seeding during surgery.