Tumor drug resistance is a leading factor of disease progression and patient prognosis.CXC chemokine ligand 8(CXCL8),also known as interleukin-8(IL-8),is a chemotactic cytokine and an important member of the tumor microenvironment.The expression level of CXCL8 in peripheral blood and tissues was increased in many malignant tumors and it is associated with drug efficacy and prognosis.CXCL8 can induce drug resistance by recruiting cell infiltration and promoting the process of epithelial-to-mesenchymal transition(EMT),cancer stem-like properties,as well as angiogenesis in tumor cells.This review focuses on the roles of CXCL8 in cancer drug resistance and offers theoretical and experimental bases for its translational applications as a biomarker to monitor efficacy and develop combination treatment regimens.