Here, we have reported foamy histiocytes noticed in the bone marrow aspiration (BMA) smears of a 14-year-old girl with the diagnosis of AML after she received 2 weeks of chemotherapy. We suggest that after the intensive chemotherapy, degradation products of blasts phagocytosed by the histiocytes may have been the cause in the increase in such histiocytes before regeneration of the bone marrow. After the remission was achieved, foamy histiocytes disappeared from BMA smears. These foamy histiocytes may be an idiosyncratic response to the chemotherapy in rare cases. Further studies about the accumulation of foamy histiocytes in bone marrow of leukemic patients received intensive chemotherapy may clarify this subject. Copyright © 2012 by Lippincott Williams & Wilkins.