Clinical study was performed on cases of local recurrence of colo-rectal cancer. The subjects of the present study included 35 cases of colon cancer and 36 cases of rectal cancer who underwent curative operation. Recurrence was observed in five out of 35 cases of colon cancer and in 11 out of 36 cases of rectal cancer. Of these cases, there were two cases of local recurrence of colon cancer including lymph node recurrence and five cases of local recurrence of rectal cancer. Through positive resection of the site of local recurrence including the lymph node in these cases of local recurrence of colo-rectal cancer, an average survival time of five years was attained, including a case showing a long survival period of 10 years following initial surgery. Because there is no other effective means of therapy for local recurrent cases of colo-rectal cancer, it is considered that early detection by careful follow-up employing various tests such as CT scanning, echography and CEA determination in the out-patient clinic followed by positive operative therapy for recurrent cases is the only available effective therapy.