Abstract: Objective: Our objective is to evaluate the efficacy of high close epirubicin combination chemtherapy in comparison with conventional dose in the treatment of non-small cell lung cancer (NSCLC) and to observe the toxicity between the two groups. Methods:30 patients with NSCLC (stage II一IV) were randomized into two groups.Each group had 15 patients. One group was treated with high dose epirubicin (HD EPI: 100mg/M2).Another group was used with conventional dose epirubicin(CD EPI: 75mg/ MZ).A ll these 30 patient s were treated with MEP (mi tomycin C+ epirubicin+ cisplatin)regimen for 2 cycles. Results: The results showed that the response rates CRR) of high close and conventional dose epirubicin groups were of 40.0% and 20.0%，respectively. The RR of HD EPI was much higher than that of CD EPI, though there was no statistical difference between the two groupe (P> 0.05).The HD EPI group had more oral mucositis. The difference was statistically significant (P<0.05).However, there was no notable statistical difference(P>0. 05)between the two groups regarding other toxicity such as gastrointestinal tract reaction, myelosuppression, phlebitis and alopecia.Obvious cardiotoxicity was not found in all patients. Conclusion; The response rate of the HD EPI group is better than that of the CD EPI group acxeording to the actual value. There is no siginificant statisitical difference betweenn the two groups concerning the main toxicity .Thus, these results are worthwhile for dinicalextensive application and further study.