Generics imatinib became an alternative treatment option for chronic myeloid leukemia (CML) patients in China. However, clinicians and patients alike harbor concerns regarding the long-term safety of generic imatinib. Patients with chronic phase CML receiving frontline imatinib treatment. A retrospective study was used to evaluate the blood concentration, effectiveness, and safety of generic in 170 CML patients. Imatinib plasma concentrations were detected by high-performance liquid chromatography-tandem mass spectrometry. Among the 170 patients, 73 (42.9%) patients treated with branded imatinib as first-line therapy, while 22 (12.9%) switched to generic imatinib during treatment due to economic considerations. No significant differences in trough concentrations between branded and generic imatinib (1549.9 ± 648.8 ng/mL vs 1479.0 ± 507.0 ng/mL; p = 0.95). During the 2-year follow-up, there were no significant differences in molecular response rates (major molecular response (MMR): 33.3% vs 37.0%; deep molecular response: 56.9% vs 42.9%, p = 0.17) between the branded and generic imatinib. Both groups showed similar rates of switching to second-generation tyrosine kinase inhibitor (11.8% vs 15.1%, p = 0.56). Furthermore, there were no significant differences in event-free survival or failure-free survival between branded and generic imatinib. Twenty-two (12.9%) switched to generic imatinib during treatment, 68.2% maintained their level of response, 27.3% improved, and only one patient (4.5%) lost MMR. There were no significant differences in the incidence of various adverse events. Generic imatinib are equally effective and safe compared to branded molecules, both for newly diagnosed patients and those who switch from branded.