We report two cases of recurrence at an anastomosis site with leakage after operation for rectal cancer. In these cases, we thought that an implantation on leakage sites should be occurring by remaining stool with cancer cell. Colorectal cancer with ileus owing to obstacle by tumor, such as our cases, has a high risk of leakage at the anastomosis site and developed a complication that increased the risk of local recurrence. In our case of colorectal cancer with ileus owing to stenosis by tumor, a treatment method including the selection of operation should be contemplated how to prevent a local recurrence.