Blood in stool one month after rectal cancer surgery is mainly considered to be related to the abnormal condition of local mucous membrane and capillary rupture, and the main reasons for the corresponding condition include mucous membrane damage around anastomosis, inflammation and tumor recurrence. 1. Mucosal injury around anastomosis: during the recovery period, the mucous membrane itself is relatively fragile, and local scratches caused during defecation will lead to bleeding. 2. Inflammation: during the recovery period, some patients need to do radiotherapy, which may cause edema of intestinal mucosa and fragile capillaries, which may cause rupture and lead to bleeding. 3. Tumor recurrence: some rectal cancers are poorly controlled, resulting in tumor recurrence, and local rupture will also cause bleeding. If bleeding occurs, it is necessary to pay attention to closely observe the specific changes. If there is constipation, it is necessary to increase dietary fiber intake in food, consume more fresh vegetables and fruits to prevent and control constipation, or take medicines such as aloe vera capsule to soften the stools. If the bleeding is not relieved, it is necessary to consult a doctor for observation and standardized treatment after diagnosis of the condition, so do not be negligent to avoid delaying the condition.