Nitric oxide (NO), is endogenously synthesized from L-arginine by nitric oxide synthase (NOS), exhibits a dual role in sensitivity to radiotherapy and chemotherapy of cancer cells. The aim of this study was to evaluate the influence of polymorphisms in NOS genes on treatment response of non-small-cell lung cancer (NSCLC) patients after radiochemotherapy. A cohort of 198 NSCLC patients treated with radiochemotherapy between 2009 and 2011 were included in this study. Genotyping analyses of 35 SNPs ( NOS2A, 21 and NOS3, 14) in each sample were conducted by using the Sequenom MassArray system. Unconditional logistic regression was performed to assess the association between treatment response and each genotype while adjusting or not for other covariates. Of 198 patients, 87 (43.9%) had objective responses, and 111(56.1%) did not respond. We observed no significant associations between treatment response and each genotype. While adjusting for other covariates, the associations were also not significant. Our results suggest that genetic variations within the NOS2A and NOS3 genes may not influence the treatment response in NSCLC patients with radiochemotherapy. Future studies in this problem are required to confirm our findings.