Background and purpose: Natural killer/T cell lymphoma in poor effects, the production of multidrug resistance is one of the reasons to reduce the chemotherapy effect or failure. This study aimed to discuss the multidrug resistance associated protein 4 (ABCC4/MRP4) gene and multidrug resistance associated protein 5 (ABCC5/MRP5) gene expression in NK/T cell lymphoma SNK-6, YTS cell lines and NK/T cell lymphoma tissues, and the relationship between the level of ABCC4/MRP4, ABCC5/MRP5 gene expression and the clinical efifcacy. Methods:Real-time lfuorescence quantitative PCR (Real time-PCR) and immunohistochemical method (IHC) were used to detect the ABCC4/MRP4, ABCC5/MRP5 gene and protein expression. Results:Compared with the normal NK cells, ABCC4/MRP4 and ABCC5/MRP5 gene in SNK-6, YTS cell lines were highly expressed (P<0.05); Compared with rhinitis tissues, the expression of ABCC4/MRP4, ABCC5/MRP5 gene was higher in the NK/T cell lymphoma tissues (P<0.05);The expression level of ABCC4/MRP4 and ABCC5/MRP5 gene was negative correlation with clinical efifcacy (P<0.05). Conclusion: The expression of ABCC4/MRP4 and ABCC5/MRP5 gene affects the of clinical efifcacy of NK/T cell lymphoma.