Out of a total of 185 cases of acute leukemia at our institution from 1967 to 1978, fifteen cases (8.1%) were identified as erythroleukemia or erythremic myelosis. The symptoms at presentation were often related to anemia (10/15 cases); the presenting hemoglobin value was lower than 10.0 gm/100 ml. Nucleated red cells were present in the peripheral blood and reticulocyte response was inappropriate to the degree of anemia. Marrow biopsy showed erythroid hyperplasia with megaloblastic and dyserythropoietic features, increase in myeloblasts greater than 5% (10/15 cases), positive PAS staining of erythroid precursors (12/12 cases), and erythrophagocytosis by abnormal erythroid precursors (6/15 cases). Abnormalities were noted in monocytic and megakaryocytic cell lines, and it was concluded that erythroleukemia is probably a stem cell disorder. Response to chemotherapy was poor with median survival of four months from initial diagnosis. Intracranial hemorrhage and bacterial or fungal infection were the most frequent cause of death.