In order to investigate the role of miR-126-5p in mediating the progression of NSCLC by targeting MTDH, NC, miR-126-5p, miR-126-5p+vector, or miR-126-5p+MTDH was transfected into SPC-A1 and A549 cells. The gene discussed is MTDH; the disease is non-small cell lung carcinoma.