Blood in the stool after colon cancer surgery depends on the situation. If it is a small amount of blood leakage in the early stage, no special treatment is needed. Because after colon resection, blood leakage from the anastomosis will occur frequently. For a small amount of blood leakage, it is fine as long as you pay attention to it. If the amount of bleeding is relatively large, medication should be given first to stop the bleeding and determine whether the bleeding is effective. If medication is ineffective, interventional treatment can be chosen to stop the bleeding through vascular embolization. If embolization is also unable to stop the bleeding, or if the bleeding is relatively large and circulatory changes occur, surgical intervention may be required to stop the bleeding through reoperation. If bleeding in stool occurs several years after surgery, it is necessary to be alert to tumor recurrence and colonoscopy is essential. Colonoscopy can diagnose whether there is tumor recurrence or bleeding caused by other diseases.