Abstract: Objective To explore the influence of leukemia inhibitory factor(LIF) on the proliferation and invasion of non-small cell lung cancer(NSCLC) cells. Methods The expression of LIF in human NSCLC tissues and adjacent tissues were detected by fluorescent quantitative PCR and Western blot. After NSCLC cell lines A549 and Z793 were treated with recombinant LIF, we detected cell proliferation by MTT assay, cell invasion by Transwell assay, and ATK/mTOR pathway by Western blot. Results LIF expression was higher in lung cancer tissues than that in the matched adjacent tissues(P=0.0078). After A549 and Z793 cell lines were treated with recombinant LIF, the tumor cells showed a significantly higher proliferation rate and invasiveness in vitro than those in control group(P<0.01); moreover, the phosphorylated AKT level was significantly elevated and the expression of mammalian target of rapamycin(mTOR), the AKT downstream targets, was obviously up-regulated. Conclusion LIF expression is significantly increased in NSCLC cells. In addition, the ectopic expression of LIF promotes cell proliferation and invasion via activating AKT/mTOR pathway.