Malignant phaeochromocytoma is defined as the presence of tumour deposits at sites that are normally devoid of chromaffin cells. We report on a 63-year-old man who had a giant malignant phaeochromocytoma of the right adrenal gland that encased the inferior vena cava. The urinary excretion rates of catecholamines and their metabolites were normal, except for normetanephrine, which was excreted at a higher rate than normal. The tumour was surgically unresectable by laparotomy. Postoperatively, the patient was given a 4-month trial of subcutaneous octreotide and intravenous meta-iodobenzylguanidine I 131. Occult lung secondary tumours were first detected by meta-iodobenzylguanidine scintigraphy after 2 years, and the patient died of bone and lung metastases 1 year later. Because phaeochromocytoma is rare, local experience in managing this disease is limited. This report alerts physicians of the methods of diagnosing and managing surgically unresectable malignant phaeochromocytoma.