Objective To explore the efficacy of postoperative radiotherapy and chemotherapy in patients with local advanced rectal cancer (LARC) and its prognostic factors. Methods A retrospective analysis of 129 patients with LARC (23 cases of ⅡA stage LARC, 10 cases of ⅡB, 7 cases of ⅡC, 5 cases of ⅢA, 60 cases of ⅢB, and 24 cases of ⅢC) receiving postoperative radiotherapy and/or chemotherapy from July 2005 to September 2010 was performed. The conformal or intensity modulated radiotherapy and fluorouracil-based chemotherapy were used. According to patients’ clinical, pathological, and therapeutic data, Kaplan Meier method was used to calculate the survival rate, log-rank single factor test was used to analyze the prognosis, receiver operating characteristic (ROC) curve method was used to calculate the cut-off point of positive lymph node rate, and Cox proportional hazards model was used to analyze the prognosis. Results The follow-up rate and median follow-up period in 129 patients were 99.23% and 39 months, respectively. The 1, 3, and 5 year overall survival (OS) rates were 90.7%, 57.4%, and 44.3% respectively and the 1, 3, and 5 year disease free survival (DFS) rates were 72.1%, 46.1%, and 41.0% respectively. Single factor analysis of the prognosis showed that lymph node grouping, CEA and CA199 levels before and after treatment, cancer nodule, differentiation, rate of positive lymph node, hemoglobin (HGB), and postoperative adjuvant chemotherapy were factors affecting the prognosis of rectal carcinoma. COX multivariate regression analysis of patients with LARC showed that there were 9 independent factors related to the prognosis, i.e. differentiation (P=0.041), depth of infiltration (P=0.046), cancer nodules (P=0.002), lymph node grouping (P=0.002), postoperative adjuvant chemotherapy (P=0.006), CA199 level before treatment (P=0.062), HGB level before treatment (P=0.001), CEA level after treatment (P=0.022), and CA199 level after treatment (P=0.000). The Wald value of lymph node grouping was the largest, followed by CA199 after treatment, HGB before treatment, cancer nodule, depth of infiltration, postoperative adjuvant chemotherapy, differentiation, CEA after treatment, and CA199 before treatment. Conclusion Before the implementation of multi discipline consultation (MDT) in our hospital, Patients with LARC who are unable to receive preoperative neoadjuvant therapy can benefit from postoperative radiotherapy combined with chemotherapy. Lymph node grouping, infiltration depth, differentiation, tumor nodule, and CEA, HGB, and CA199 levels are significantly correlated to OS and DFS.