Purpose: This analysis was conducted to evaluate the cost-effectiveness of gemcitabine-cisplatin chemotherapy for non small-cell lung cancer patients in an outpatient setting compared with the traditional inpatient setting. Methods: A cost-effective analysis was conducted from a societal perspective. The effects of treatment, which was measured as an adverse event rate, were abstracted from a published literature search and empirical data from one university hospital. The costs included both direct and indirect costs. Direct costs included hospitalizations, outpatient visits, and lab tests. Pharmaceutical costs were excluded in analysis because they were same for both options. Indirect costs included productivity loss of patients as well as care-givers. In order to determine the robustness of the results, sensitivity analysis on treatment protocol was conducted. Results: Literature search showed no difference in adverse effect rates between inpatient treatment protocol and outpatient treatment protocol. Therefore, this analysis is a cost-minimization analysis. Cost-savings in the outpatient setting was 555,936 won for one treatment cycle. Our sensitivity analysis indicated that the outpatient chemotherapy still showed cost-savings, regardless of changes in treatment protocol. Conclusion: The outpatient gemcitabine-cisplatin chemotherapy for non small-cell lung cancer resulted in cost savings compared to inpatient chemotherapy. More importantly, outpatient chemotherapy could improve the utilization of health service resources in terms of available beds.