A sensitive, rapid, simple and economical ultra-performance liquid chromatography–tandem mass spectro-metric method (UPLC–MS/MS) was developed and validated for simultaneous determination of imatinib, dasatinib and nilotinib in human plasma using gliquidone as intal standard (IS). Liquid-liquid extraction method with ethyl acetate was used for sample pre-treatment. The separation was performed on an Xtimate Phenyl column using isocratic mobile phase consisting of A (aqueous phase: 0.15% formic acid and 0.05% ammonium acetate)and B(organic phase:acetonitrile)(A:B=40:60,v/v).The flow rate was 0.25 mL/min and the total run time was 6 min. The multiple reaction monitoring (MRM) transitions, m/z 494.5→394.5 for imatinib, 488.7→401.5 for dasatinib, 530.7→289.5 for nilotinib and 528.5→403.4 for IS, were chosen to achieve high selectivity in the simultaneous analyses. The method exhibited great improvement in sensitivity and good linearity over the concentration range of 2.6–5250.0 ng/mL for imatinib, 2.0–490.0 ng/mL for dasatinib,and 2.4–4700.0 ng/mL for nilotinib.The method showed acceptable results on sensitivity,specificity, recovery, precision, accuracy and stability tests. This UPLC–MS/MS assay was successfully used for human plasma samples analysis and no significant differences were found in imatinib steady-state trough concentra-tions among the SLC22A5?1889T>C or SLCO1B3 699G>A genotypes(P>0.05).This validated method can provide support for clinical therapeutic drug monitoring and pharmacokinetic investigations of these three tyrosine kinase inhibitors(TKIs).