Chronic myeloid leukemia (CML) is a malignant disease of hematopoietic systems, belongs to the proliferative marrow syndrome group, and is characterized by the proliferation of differentiated granulocytes of cell lines. Nowadays, Vietnam has some drugs for treatment of CML, but the appearance of genetic variants is likely to increase the drug resistance of patients. Therefore, the identification of variants plays an important role in CML treatment. In this study, the authors extracted RNA on BCR/ABL1 gene, which causes CML disease, from marrow samples of ten CML patients at National Institute of Hematology and Blood Transfusion (NIHBT). After that, RNA samples of each patient was sequenced by using Illumina MiSeq sequencing technology, then they carried out preprocessing data, aligned high quality sequences to the reference genome, and identified variants of the patient. The results showed that there were 18 variants detected from ten CML patients, including 2 variants at loci 133747603,133747604 found on 8 patients; 3 variants at loci 133755142,133755143,133755146 found on 6 patients. Among them, four variants 133738357, 133748391, 133738356, 133759413 were annotated on dbSNP database of NCBI (National Center for Biotechnology Information); remarkably, 2 variants at loci 133738357 (rs121913461) and 133748391 (rs121913457) were reported to be resistant to Imatinib drug in CML patients. The results in this study will provide valuable information for further studies into the roles of the variants with drug resistance.