目的　探讨保肛术后 ,可能导致复发的各种因素。方法　通过复发病例的分析 ,寻找出复发的主要因素。结果　除因癌细胞脱落造成种植等因素外 ,最主要原因是切缘与癌下缘距离过近。结论　保肛手术应避免癌细胞脱落、种植而造成的复发 ;直肠癌保肛手术要针对具体病例进行 ;下切缘厘米数应视不同情况决定 Objective To explore the factors that may lead to recurrence after anal sphincter preservation. Methods Through the analysis of recurrent cases, the main factors for recurrence were found. Results In addition to factors such as planting due to the loss of cancer cells, the most important reason was that the cutting margin was too close to the lower edge of the cancer. Conclusion Anus-preserving operation should avoid the recurrence of cancer cell shedding and planting; rectal cancer should be performed on specific cases for sphincter preservation surgery; the number of centimeters of the lower incision should be determined according to different conditions.