SummaryIn a 55 years old man repeated blood tests detected a haemologic syndrom characterized by :1°Polyglobulia ;2°Very low haemoglobin ;3°Definite microcytosis ;4°Numerous abnormalities of the red cells.The patient had achlorhydrie and his bone marrow showed only a slight erythroblastic reaction. Liver extracts exagerated the tendancy to polyglobulia. Martial treatment increased the haemoglobin content of the blood.It is difficult to classify this syndrome in the group of microcytic anaemias. The hyperglobulia may be the characteristic pecularity of this case; but it may as well be the consequence of an exagerated blood regeneration.