Seventy patients with acute promyelocytic leukemia (APL) were entered in this study. Fifty-seven cases received all-trans retinoic acid (RA) as sole agent and 48 cases (84.2%) attained complete remission (CR) in about 42 days. While the other 8 cases (14%) obtained partial remission (PR) during some time. Thirteen patients received combinations of RA and chemotherapy. 9 cases (69.2%) attained CR in about two months and 4 other cases (30.8%) got PR. Total CR rate reached 95.9% after continuing the treatment. Fifty cases were closely followed after CR. Three kinds of continuation therapy were administered including RA as sole agent (Group A), chemotherapy alone (Group B) and RA and chemotherapy alternatively (Group C). The results showed Group C gave the longest duration of CR and longest duration of survival.