Assessing the lung cancer treatment costs is necessary in order to estimate the budget impact of new interventions and therapeutic innovations. However, there are few studies regarding the use of resources and costs associated with treatment of lung cancer patients, not only in Serbia, but internationally. The aim of this paper was to assess the hospital costs of diagnosing and treating patients with stage IIIB and IV non-small cell lung cancer. Analysis of costs of care, services, medications and medical supplies, as well as of total hospital costs, was performed. Patients diagnosed with stage IIIB or IV NSCLC in the Institute during the year 2013 were enrolled in the study. A total of 187 patients with stage IIIB or IV NSCLC were analyzed. Total hospital costs were 506.970€, of which nearly two thirds was accounted to costs of services and medications. The mean cost per patient with adenocarcinoma was 3.075€, and for squamous cell lung carcinoma patient 1.943€. Statistically significant difference was shown when comparing mean hospital costs between patients in stage IIIB and stage IV adenocarcinoma, where this cost is higher in patients with stage IIIB. Mean hospital cost per female patient was nearly double as high that of the male patients, although without statistically significant difference. The mean cost for all adenocarcinoma patients was 1.317€, and for only four patients treated with TKI therapy 21.233€. This cost analysis could provide useful information in terms of budget impact of different lung cancer treatments and innovations in Serbia and corresponding developing countries.