A survival benefit of patients with inoperable non-small cell lung cancer has been reported since a development of new therapeutic agents in the 1990's. However, multivariate analyses of patients have not been evaluated. The aim of this study is to identify prognostic factors in the long-term survivors who had been treated with chemotherapy using these new agents and/or radiotherapy. A retrospective study and clinical analysis of 121 inoperable nonsmall cell lung cancer patients were conducted. Fifteen cases (male: 9, female: 6) with a survival of more than 2 years were revealed. Regarding clinical variables between the 15 cases and others, an early nodal (N) status, a high serum protein level, a good performance status (PS) and those having first-line chemotherapy or radiotherapy were all identified as significant prognostic factors for the long-term survivors. Multivariate analyses also revealed that an early N status, a good PS, female gender and chemotherapy and/or radiotherapy were associated with the long-term survivors. These results suggest that patients with inoperable non-small cell lung cancer should be considered for appropriate treatments including new chemotherapeutic agents.