Background and objective hTis study aims to explore the effect of epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKIs) on the lymphangiogenesis of lung cancer withEGFR mutation, as well as to determine the function of EGFR targeted therapy in relation to the inhibition of lymphangiogenesis during lung cancer treatment.Methods hTeEGFR double mutant lung cancer cell line NCI-H1975 is used to construct lung cancer xenogratf models. hTe models are divided into two groups:the solvent control group and the EGFR-TKI treatment group. Each group includes ifve mice. hTe inhibitory effect of EGFR-TKI on the growth of transplanted tumors was observed. Immunohistochemical method and lymphatic endothelium speciifc antibody D2-40 were used in the experiment to observe the inlfuence of EGFR-TKI on lymphangiogenesis in lung cancer.Results hTe weight and relative volume of tumors in the EGFR-TKI treated group were less than those in the solvent control group. hTe average lymphatic ves-sel density of EGFR-TKI-treated mice was 6.44 per case. hTis value was 10.70 per case in the solvent control group. Lower density of lymphangiogenesis was found in the EGFR-TKI treated group (P=0.023). hTe area and longest diameter of neonatal lymphatic vessel of the EGFR-TKI treated group were less than those of the solvent control group. Moreover, EGFR-TKI exhibited no signiifcant effect on the invasion of tumor cells into the lymphatic vessel (P=0.519).Conclusion EGFR-TKI can inhibit lymphangiogenesis inEGFR mutant lung cancer while suppressing vessel diameter and expansion area.