A 17-year-old boy was admitted to hospital because of severe hypertension (200/130 mmHg), headache, irritability, sweating, etc. Initial biochemical tests suggested pheochromocytoma, being treated with nifedipina, clonidina and propranolol.On reporting exposure to mercury vapour, he underwent twenty-four-hour urine screening and measurement of blood mercury which confirmed intoxication. The patient received courses of chelation therapy with dimercaprol (BAL) and penicillamine with remission of symptoms and normalisation of hypertension after 2 months. This case is relevant to current practice regarding similarity between mercury intoxication and hypertension secondary to pheochromocytoma.