Objective To investigate prospectively effects of different drainage methods on preventing anastomotie leakage after Dixon operation in rectal carcinomas.Methods During the period of January 2002 to January 2007,450 patients with rectal carcinomas received Dixon operation.They were divided into three groups ( group A,B,and C) in order of admission.Presacral drainage was done in Group A,presaeral drainage + drainage through anus with one tubes in Group B,and presacral drainage + drainage through anus with two tubes in Group C.The postoperative complications of three groups were observed.Results There was 7.33% (11/150) ,8.00% (12/150) and 6.67% (10/150) wound infection in group A,B and C respectively.8.67% (13/150),6.67% (10/150) and 1.33% (2/150) anastomotic leakage occurred in group A,B and C respectively.Three groups had a similar wound infection ineidence(P ＞0.05).The occurrence of anastomotic leakage in group C was statistically lower than that in group A and B ( P ＜ 0.05 ).Conclusion Presacral drainage + drainage through anus with two tubes can effectively prevent anastomotic leakage after Dixon operation in rectal carcinomas.