Overexpression of the epidermal growth factor receptor (EGFR) has been identified as a common component of various cancer types including lung cancer. Recently morpholino oligonucleotides appeared as a promising modification for antisense applications with few toxic effects and their stability. We investigated the effect of EGFR antisense morpholino oligomer on non-small cell lung cancer (NSCLC) cell line by evaluating EGFR mRNA, protein product and cell proliferation. The EGFR antisense morpholino oligomer was designed to target the translation start site in the EGFR mRNA. The four base-mismatch morphlino oligomer was designed as a control for EGFR antisense morpholino oligomer. These morpholino oligomers were introduced into NCI-H125 cell line which showed overexpression of EGFR. The EGFR mRNA and protein expression were quantified by real time RT-PCR and ELISA, respectively. The significant repression in both EGFR mRNA and protein expression was observed for three days after single treatment with EGFR antisense morpholino oligomer. Furthermore, the growth of NCI-H125 cell line was significantly inhibited with treatment by EGFR antisense morpholino oligomer. Our results indicate that EGFR antisense morpholino oligomer represses the EGFR expression at both mRNA and protein level and inhibits the proliferation of NSCLC cell line suggesting that it may be a promising strategy as one of antisense therapies for NSCLC.