Cytochemical parameters of intracellular metabolism of leukemia cells and bone marrow polyamines were studied in 113 acute lymphoblastic leukemia patients aged from 1 to 14 years. The parameters analyzed characterized the severity of the disease course, cytostatic therapy effectiveness and primary resistance. It is shown that determination of biochemical and cytochemical criteria before the beginning of acute lymphoblastic leukemia therapy may be conducive to the correct choice of treatment.