Oncohaematology is one of the most dynamic areas of medicine, which has been actively developing in the last 10 years. Over the years, many new scientific facts have been discovered which largely changed the fundamental concepts in oncology. The results obtained from modern molecular biological methods helped scientists to explain the structural changes in the genome of the cells, which are responsible for initiation of a tumour and tumour growth. In this study, we investigated the frequency of HLA class I (HLA-A and -B) and class II (HLA-DRB1) genes in patients with oncohematological, residing in Kazakhstan. The study enrolled 3740 participants: 3621 healthy blood donors considered as a control group (of them HLA-A – 3621; B- 3607; Cw- 3582; DRB1-3595; DQB1-3576) and 633 patients with oncohematological diseases. HLA-typing (HLA-A, -B, -С, -DRB1 and -DQB1) for both groups was performed by a molecular genetic method using a kit from Protrans (Protrans, Germany). The study done to investigate the distribution of the HLA antigens for each oncohematological disease. Based on AML patients’ results, there is an association between the presence of the genes such as HLA-A*31, B*37 and the development of AML. The HLA antigens including HLA-A*30, В*44, C*16, DRB1*07, *16 marked with the development of ALL, whereas the genes such as HLA-A*11, HLA-B*18, *41, *47 *73 considered as genetic markers for the development of CML. In addition, the genes such as HLA-В*35, HLA- DRB1*11,*15 displayed the link between these antigens and the development of MDS, whereas the existence of HLA-A*24, HLA-В*40, *54, HLA-DRB1*14 antigens among AA patients revealed the association between these antigens and the development of this pathology. In addition, this study found that the presence of some HLA antigens in the genome has a protective role against oncohematological pathologies. For example, for AML- HLA-A*02, B*27, C*02, DRB1*01, *04, DQB1*06 genes; for ALL- HLA-А*02, С*02, DQB1*06 genes; for CML- HLA-А*01, HLA-С*02, *06 genes; for MDS- HLA-A*02, HLA-C*07 genes; for AA- HLA-С*02, *05, *07, *12, HLA-DRB1*03, *04, *07 genes. The HLA typing results can be used to study different diseases associated with the HLA antigens.