This study is suggested to patients with superficial medium or distal rectal tumors. The lesion was identified and demarcated using white-light endoscopy, magnifying endoscopy, and chromoendoscopy. Then, marking around the lesions was performed. Local injection was made using injection needle, and then mucosal incision was performed around the lesion using endo-knives. Submucosal dissection was performed using endo-knives. Hemostasis and vessel coagulation were practiced using primary hemostatic forceps during the procedure.