Objective：To explore of the effect of miRNA-451 on invasion，metastasis and apoptosis of human A549 lung cancer cells. Methods：Hsa-miRNA-451 sequence was found in miRBase database and two oligonucleotides were designed according to the se－quence. The targeted gene was annealed and cloned to eukaryotic expression vector plasmid pGenesil-1.1 thus miRNA-451 eukaryotic expression vector was built（pGenesil-1.1-of miRNA-451 plasmid）. PGenesil-1.1-miRNA-451 and pGenesil-1.1-control plasmid were transfected into human A549 lung cancer cells and stably expressed pGenesil-1.1-miRNA-451 and pGenesil-1.1-control cell lines were established after being selected by G418. Flow cytometry was employed to detect cell apoptosis，Transwell chamber to detect miRNA-451 cell invasion and cell scratch assay to detect cell metastasis. Results：Sequencing showed that miRNA-451 eukary－otic expression plasmids were successfully constructed. Cell invasion and metastasis were inhibited in stably expressed pGenesil-1.1-miRNA-451 cell lines compared with those in untreated human A549 lung cancer cells and stably expressed pGenesil-1.1-control cell lines，however，there was no change in cell apoptosis（P >0.05）. Conclusion：miRNA-451 has significant inhibitory effect on in－vasion and metastasis of human A549 lung cancer cell，however，not on cell apoptosis.