An anal fistula must be treated by surgery, that is, through surgery. Because an anal fistula is an infected tube that connects the anal canal, rectum and perianal skin, medication is only able to relieve the pain and pus symptoms that manifest during an acute attack of an anal fistula, and cannot achieve the goal of curing it. Surgical treatment is the only way to cure a fistula. For low-grade fistulas, direct fistulotomy can be performed to cure the fistula; for high-grade fistulas and submucosal rectal fistulas, fistulotomy with internal stitches can be performed because of the complex shape of the fistula and the passage through the anal raphe. Long-term untreated or untreated fistulas have a certain tendency to become cancerous and should be given clinical attention. In addition, patients with severe underlying conditions, such as heart failure, respiratory failure, and renal failure, are recommended to be treated conservatively with medications to control the number of anal fistula episodes.