Povidone-iodine is not a cure for anal fistula, it can be used to disinfect the skin near the fistula, but it does not have the efficacy of curing anal fistula. Povidone-iodine is used clinically as an antiseptic disinfectant for skin and mucous membranes, which can be broad-spectrum, including bacterial organisms, fungi, protozoa and some viruses, and it can also be used for preoperative disinfection of the skin at the site of the injection, disinfection of the instrument immersion and disinfection of the vagina before the operation. An anal fistula is formed when a perianal abscess collapses and infects the tissues around the anus. The condition is more common in young people, but can occur at any age. A common symptom of anal fistula is the frequent discharge of foul-smelling pus from the perianal area, which is usually preceded by a period of perianal pain, with an abscess forming at the same time, which recurs intermittently and lasts for a long time. Anal fistula requires surgical treatment in order to be cured radically, the main purpose of which is to drain the pus from the fistula and remove the fistula, which needs to be performed under general anesthesia. Surgery will be a silicone rubber hanging line (its thickness, toughness and rubber band similar) through the fistula, the two ends of the tie, can make the pus, necrotic tissue discharge, and then slow down the inflammation, the treatment process requires the use of antibiotics. Therefore, it is recommended that patients with anal fistula should go to the hospital as soon as possible for examination and treatment under the guidance of a professional doctor to avoid delays.