Objective To investigate the risk factors for locally recurrent rectal cancer after radical resection.Methods The clinical data of 50 locally recurrent rectal cancer patients (recurrent group) and 100 matched controls (control group) who received radical resection at the Sixth Affiliated Hospital of Sun Yat-Sen university from January 2000 to March 2009 were retrospectively analyzed.Factors including tumor location,postoperative chemotherapy,tumor differentiation,vascular or neural invasion,T stage,tumor diameter,number of lymph nodes dissected and number of positive lymph nodes of the 2 groups were analysed by univariate analysis,and factors correlated with tumor recurrence were screened out.All data were analyzed using the chi-square test,t test,Wilcoxon test or Logistic regression analysis.Results All the patients were followed up till January 2013,and the median time of follow-up was 52 months.Twenty-two patients in the recurrent group and 32 patients in the control group died during the follow-up.The results of univariate analysis showed that there were significant differences in tumor location and T stage between the 2 groups (x2 =6.407,9.652,P ＜ 0.05).There were no significant differences in postoperative chemotherapy,tumor differentiation,vascular and neural invasion,tumor diameter,number of lymph nodes dissected and number of positive lymph nodes between the 2 groups (x2 =1.349,0.342,0.656,Z =7142.5,8214.5,7241.5,P ＞ 0.05).The results of multivariate analysis showed that tumor location and T stage were the factors correlated with the tumor recurrence after radical resection (Wald =3.954,5.615,P ＜ 0.05).Compared with upper rectal cancer,the local recurrence rate was not significantly different in the middle rectal cancer (OR =1.893,P ＞ 0.05),whereas the lower rectal cancer had a higher local recurrence rate (OR =3.201,P ＜0.05).Compared with patients in T2 stage,the local recurrence rate was not significantly different in patients in T3 stage (OR =4.913,P ＞0.05),while patients in T4 stage had a higher local recurrence rate (OR =16.103,P ＜ 0.05).Conclusion Locally recurrent rectal cancer is closely related to tumor location and T stage,which indicates that factors reflecting the extent of surgical resection (such as circumferential margin) are of great importance in assessing the prognosis and making subsequent treatment schedule.