Background: We surveyed prognostic biomarkers for resectable non-small cell lung cancer (NSCLC). Methods: We obtained preoperative serum from 109 patients admitted to our facility, and measured the levels of hepatocyte growth factor (HGF), interleukin-6 (IL-6), and nicotinamide N–methytransferase (NNMT) in the sera by the ELISA method. We also examined the clinical backgrounds of the patients. Results: The median HGF and IL-6 contents in sera from 109 patients were 860 pg/ml and 2.7 pg/ml, respectively. Analysis of survival curves indicated that HGF or IL-6 levels higher than the median were associated with poor overall survival (HGF, P = 0.019; IL-6, P = 0.002). On the other hand, carcinoembryonic antigen (CEA), a known tumor marker, and NNMT, which we found to be a candidate tumor marker, exhibited no correlation with the prognosis. The tumor status (pT factor) and stage were strong prognostic indicators (P < 0.001). In addition, we analyzed stage III lung cancer alone. Higher HGF or IL-6 levels were associated with poor overall survival (HGF, P = 0.016; IL-6, P = 0.013). Disease-free survival was also affected by these cytokine contents, but not statistically significantly. The prognosis of patients with adenocarcinomas (ADC) was better than that of patients with other histological types. However, the pT factor and nodal status (pN factor) were not associated with the survival of stage III patients. Conclusions: The levels of HGF and IL-6 in serum could be useful prognostic indicator of the survival of stage III NSCLC patients undergoing surgery and chemotherapy.