Objective · To investigate the effects of the lymph node ratio (LNR) on overall survival and disease free survival after surgeries in patients with locally advanced rectal cancer. Methods · We retrospectively analyzed clinical data of 299 patients who underwent curative resection for locally advanced rectal cancer (T3/4 or N+) between July 2005 and March 2010. The best cutoff value for predicting the survival outcome was obtained with ROC curve analysis method. Kaplan-Meier method was used to perform survival analysis and Cox regression models were used to conduct multivariate analysis. Results · The 5-year overall survival rate and 5-year disease free survival rate were 30% and 25% in 299 cases of locally advanced rectal cancer. Lymph node ratio of 0.21 (21%) could favorably predict the survival and prognosis. The median overall and disease-free survival rates were significantly higher in the low LNR group (LNR ≤0.21) than in the high LNR group (LNR＞0.21) (59.6 vs 39.5months, P=0.000; 30.0 vs 19.5 months, P =0.004). Univariate and multivariate analyses showed that besides pathological type, pathological differentiation, lymphovascular invasion, number of lymph nodes examined, pN stage, and TNM stage, LNR was an important factor for predicting the prognosis. Conclusion · LNR is an important factor for predicting the overall survival and disease free survival after surgeries in patients with locally advanced rectal cancer.