With the development of new technologies of automated blood analysis, there are new opportunities to assess the prognosis of acute leukemia in response to chemotherapy. The aim of the study was to evaluate of elimination of blast cells and the degree of bone marrow recovery after chemotherapy with the help of modern technologies of automated analysis. Material and methods. As the object of the study, venous blood samples were used in 29 patients with primary OML, taken on an empty stomach in vacuum tubes with anticoagulant with K2-EDTA. The investigations were carried out on hematological analyzers (ADVIA 2120/2120i (Siemens) and CELL-DYN Sapphire (Abbott Lab, S. A.) and the Cytomics FC500 flow cytometer (Beckman Coulter) using the CYTODIFFTM monoclonal antibody kit. The number of MPO — positive blast cells was carried out using sets of Diahem-Cytostain-MPO manufacturer — «NPF-Abris +». During the first induction course in the majority of patients, samples were analyzed in the dynamics of 1, 4—6, 7—8, 15—16, 21—23, 28—35 days since the start of chemotherapy. During the course of consolidation, another 36—43 days were added to the previous measurement points. According to the results of the first course of induction therapy, two groups of patients were identified: 1st (n=14, age from 24 to 83 years) with blasts <5% in the bone marrow and 2nd (n=13, age from 37 to 79 years) with blasts >5% in the bone marrow. Consolidation therapy courses were conducted in patients with complete remission. These patients are allocated to a 3rd group. To statistically analyze the results of the study, the program GraphPad Prism (GraphPad Software, Inc., USA) was used. When comparing groups we used the criterion of Manny-Whitney test for two independent groups and the test of Freidman for three or more dependent groups. Results. Control elimination of blasts using a set of CYTODIFFTM parameter % Xn (myeloblasts) showed that in the 1st group there was a significant decrease %Xn already 7-8 day of chemotherapy (p<0.05), in the 2nd group %Xn did not change significantly. The dynamics of reduction of blast cells in the parameter LUC hematological analyzer ADVIA 2120/2120i possible only in patients with initially high value of LUC. WBC, PLT recovered to the level of normal values only in the 1st group. The increase in %rP (reticulated platelets) preceded the restoration of PLT for 7-10 days. % RET #RET was restored to normal in both groups. Conclusions. Modern technologies of automated blood analysis allow assessing the elimination of blast cells and the degree of bone marrow recovery after chemotherapy.