The wound after anal fistula surgery is relatively large and deep, so the incision needs to be plugged drainage gauze, drainage gauze’s role is mainly to drain the exudate out of the incision, and can not stop the production of exudate, so the plugged drainage gauze will still have exudate out. After anal fistula surgery, the wound is large, in the case of its not completely healed, the wound will continue to appear secretion, especially when the wound is infected. The role of placing drainage gauze is to drain the exudate formed in the wound out of the wound and to prevent the formation of pseudo-healing. The placement of drainage strips within the wound does not prevent the formation of exudate, with the gradual healing of the wound, the exudate is gradually reduced, until complete healing. It is recommended that patients change the medication on time after anal fistula surgery to avoid wound infection and the formation of pseudo healing, regular review, if there is any abnormal perianal manifestations and questions, can consult the doctor and give treatment and guidance.