The wound is still bleeding 4 months after the anal fistula surgery, which may be related to constipation, wound infection, recurrence of anal fistula and other reasons. 1. constipation: when patients have difficulty defecating, constipation, etc., due to the dryness and hardness of the stool, the process of defecation force may lead to anal tearing, resulting in wound bleeding, pain and so on. 2. Wound infection: because the anal fistula is a contaminated wound, daily defecation, urination and other behaviors may cause wound infection, which may cause wound bleeding, pain, redness and swelling, and in severe cases may also cause wound abscess. 3. anal fistula recurrence: when the patient’s surgical treatment is incomplete or recurrence of anal fistula, may cause wound bleeding, pain, pus and so on. It is recommended that the patient timely medical review, identify the cause of the early targeted treatment to avoid aggravation of the condition; pay attention to personal hygiene in life, pay attention to post-operative care, timely cleaning and disinfection of the perianal area after defecation.