The analysis has been presented of the treatment of 35 patients (mainly middle-aged) with acute non-lymphoblastic leukemia, 27 of them untreated. Repeated 2-3-week courses of subcutaneous injections of cytarabine were used (10 mg/m2, twice a day). A total of 5 complete and 4 partial remissions were recorded. The frequency of complete remissions among the patients who received 2 and more courses of the drug therapy comprised 38.8%. Complete remissions were observed in primary patients with initially lowered or normal leucocyte count in the blood, with partially retained granulocytopoiesis, and a relatively slow progressing of the disease. The mechanisms of action of low doses of cytarabine has been considered.