A 4-day-old patient with Down syndrome (DS) visited out patient department (OPD) because of jaundice and VSD. Peripheral blood smear showed 21% of myeloblast. After 4 weeks of observation, WBC count was 55,100/mm3 (blast 90%). BM aspirate showed AML (M7) and treatment was started with low dose Ara-C (20 mg/m2 for 21 days). After remission, maintenance therapy was done with low dose Ara-C (16 mg/m2 for 21 days), 6-TG (40 mg/m2 for 21 days) and low dose IL-2 (0.5 106U/m2 for 21 days) alternatively for 2 years. The patient remained in complete remission and VSD was corrected at 9 months of age. This case shows that remission can be achieved with low dose Ara-C and it can be maintained thereafter with low dose Ara-C, 6-TG and IL-2. Low dose IL-2 has the advantage of selectively activating immune cells with high affinity receptors, low treatment related morbidity, good compliance which can be injected at OPD. As the patients with DS have defect in IL-2 secretion, IL-2 may have an beneficial effects on treating AML in DS.