Bleeding from the inner mouth after perianal abscess surgery may be due to unrecovered trauma, trauma infection, and recurrence of perianal abscess. 1. The wound is not recovered: perianal abscess surgery will cause surgical wounds on the anal area, and the patient’s postoperative activities may cause the wound to crack, which will lead to the occurrence of postoperative bleeding. 2. Wound infection: Improper postoperative care may lead to wound infection. It may cause pain and swelling in the anal area, and under the stimulation of inflammation, the wound will secrete pus mixed with blood, resulting in non-healing of the wound. 3. Perianal abscess recurrence: bleeding after perianal abscess surgery may also be due to perianal abscess intraoperative drainage, cleaning is not complete, and recurrence. Hemorrhoids, anal fistula and rectal tumors can also lead to the occurrence of bleeding from the anal opening, so it is recommended that the patient should consult a doctor in time for examination, clear diagnosis and reasonable treatment.