Pulmonary hemosiderosis was investigated on sixty necropsied cases, 20 of them of Chagas' myocarditis, 20 of non chagasic cardiopathies and 20 of subjects with no history of cardiac failure. The incidence of hemosiderosis was 759: among the cases of Chagas' myocarditis, 80% in the other cardiopathies and 45% in people without cardiac disease. The amount of iron in the lung tissue (Pearls' and Tirmann - Schmelzers' reactions) was usually moderate to mild in all cases. It is concluded that pulmonary hemosiderosis in Chagas' disease seems to result from passive congestion and does not represent a peculiar feature of that disease as has been claimed by others.