Cardiac-related death of HIV-positive patients is not rare. The etiology of AIDS-associated dilated cardiomyopathies often remains unknown, even at autopsy. We report an observation associated to a severe deficit in selenium. The patient had been diagnosed as HIV-positive 2 years before. He presented Pneumocystis carinii pneumonia then Cryptococcus meningitis. Two months later he was hospitalized for pancreatitis and cachexia. He presented global heart failure that lead to death. No microorganism was found in myocardium at autopsy but plasma selenium was dramatically decreased (24 micrograms/L). The deficit in selenium has been associated to a dilated cardiomyopathy in non-AIDS patients. HIV-positive patients have an early decrease in plasma selenium, this concentration is dramatically decreased in malnourished patients. Selenium deficit might be the cause of some of the AIDS-related dilated cardiomyopathies and selenium supplementation might be useful in these patients.