A double-blind, placebo-controlled randomized study of danazol was performed to determine if the drug has a therapeutic effect in patients with myelodysplastic syndromes (MDS). Fifty evaluable patients with MDS were randomized to receive, a single daily oral dose of either danazol (600 mg/day) or matching placebo. Treatment was continued, when possible, for a period of 6 months. Response was based on clinical course, peripheral blood counts with white blood cells differential, platelet, reticulocyte at specified intervals. Repeat bone marrow aspirates and biopsy were also done. Significant differences was observed between the treatment groups in response to test drug. Increase in hemoglobin, granulocytes, platelets and improvement in survival was noted in danazol group. Side effects were minimal. Our study suggests that danazol exerts a beneficial therapeutic effect in patients with MDS.