Thirty cases of childhood acute nonlymphocytic leukemia (ANLL) have been treated with intermittent, intensive multi-drug combinations during the past 5 years. Three patients never attained complete remission (CR) and 3 died of complications after less than one month of treatment. Twenty-four (86.7 %) attained CR with a median CCR of 26 months. The median for disease-free survival (DFS) among the total 30 cases was 15 months. Twelve out of the 24 CR patients have been disease-free for longer than 16 months, indicating significantly improved therapeutic results. Among the factors affecting prognosis, we found that patients with certain clonal abnormalities of leukemic cells and initial leukocytosis (greater than 40,000/microliter) had poor prognosis. Further revision of treatment should be considered for patients with high-risk ANLL.