After the discovery of the bcr -abl fusion gene, which shows the tyrosine kinase activity responsible for its etiology in Chronic Myeloid Leukemia (CML), longer survival times have been achieved with the discovery of drugs that inhibit this activity. The de velopment of resistance to treatment with these drugs over time paved the way for the development of second and third generation agents. In this study, we aimed to evaluate the effects of patients receiving second generation tyrosine kinase inhibitor (TKI) - bosutinib - treatment on clinical, laboratory, molecular response, side effect profile and mortality in our center. Seventeen patients who were started on bosutinib therapy for CML were included in the study. The order in which the treatment was initiated, the clinical, laboratory and molecular response status of the patients were retrospectively scanned from electronic patient records. The data obtained were compared according to the order of initiation of the drugs of the patients. While no significant difference was observed among the second-line (n=2), third-line (n=7) and fourth-line (n=8) bosutinib treated patients in terms of age, gender, number of comorbidities, and duration of bosutinib treatment, there was a significant difference between the ages of CML diagnosis. There was no significant difference with the order of initiation of the drug and mol ecular response and side effect profile. The overall survival of the patients was 43.38 ± 4.98 months (95% CI: 33.62 – 53.16 months). Conclusion: It was observed that the use of bosutinib treatment was safe in all age groups at each initiation order and provide a stable molecular response. Since it does not have a side-effect profile that would limit its use, it should be considered as a preferred molecule in CML treatment.