Objective:To explore the expression of microRNA-335(miR-335) in non-small cell lung cancer(NSCLC) and its effect on migration,invasion and proliferation of NSCLC cell. Methods:Real-time quantitative PCR was used to detecte and compare the expression of microRNA-335 in 12 pairs of non-small cell lung cancer,adjacent normal tissue,NSCLC cell line SPCA-1 and normal epithelium cell line 16HBE. The expression of miR-335 in SPCA-1 cell was down-regulated by anti-miR-335 transient transfection with Lipofectamine 2000,and the effect was identified by real-time quantitative PCR. Cell migration and invasion was measured in vitro by wound healing assay and transwell assay. The influence of miR-335 on SPCA-1 cell proliferation was detected by MTT rassay and colony formation assay. Results:Compared with adjacent normal tissues,miR-335 in non-small cell lung cancer was significantly up-regulated(P < 0.05). Smilar to that,the expression of miR-335 was significantly increased in SPCA-1 cell compared to 16HBE cell(P < 0.05). The miR-335 expression of SPCA-1 cell was significantly down-regulated 24 hours after anti-miR-335 transfection(P < 0.01). In SPCA-1 cell,decreased miR-335 significantly inhibited cell migration and invasion,with the inhibiting rates of (42.8 ± 2.7)%(P < 0.01) and (73.25 ± 4.4)% (P < 0.01),respectively. But,no effect on SPCA-1 cell proliferation was observed when the expession of miR-335 was inhibited. Conclusion:The expression of miR-335 is up-regulated in NSCLC. Down-regulating expression of miR-335 significantly inhibites migration and invasion of SPCA-1 cell while has no effct on cell proliferation.