Objctive To explore the effect of positive lymph nodes ratio (LNR) on prognosis of patients with non-small cell lung cancer (NSCLC). Methods Clinical data of 432 NSCLC patients undergoing radical surgery for lung cancer and systemic lymph node dissection in our hospital from January 2010-2013 were retrospectively analyzed. There were 316 males and 116 females with age of 39-84 (57.59±9.16) years. Among 432 patients, 229 (53.0%) were classified as N0 based on pathological staging of lymph nodes, 104 (24.1%) as N1 and 99 (22.9%) as N2. Kaplan-Meier curve and COX multi-factor regression model were used to evaluate the correlation between the clinical data and patients' survival. Results Five lymph nodes on average (range, 1-52) were removed in each patient. Kaplan-Meier survival curves showed that the higher the staging of positive lymph nodes was, the shorter the patients' overall survival and disease-free survival were (P<0.001). Survival analysis showed that the LNR was closely associated with disease-free survival and overall survival (P<0.001). COX multivariate analysis revealed that the LNR staging was an independent risk factor of prognosis of NSCLC. Conclusion LNR is an independent prognostic factor of NSCLC, and can be used to improve lymph node staging in standards for NSCLC staging in the future.