A hard lump between the anus and the pubic area is first considered to be a perianal abscess, which is a purulent inflammation of the anal canal and the perirectum caused by an infection of the anal glands. Perianal abscesses can be divided into low abscesses and high abscesses according to the location of the abscess. If a patient can feel a hard mass between the anus and the pubic area, the first consideration is a low abscess. Perianal abscess needs to be treated surgically in order to be cured. During surgery, the abscess cavity should be opened and drained first, and then the anal saphenous fossa that causes the infection should be found through the probe, and then the anal saphenous fossa should be opened to make the incision grow again, so that the perianal abscess can be cured at once and the secondary anal fistula surgery can be avoided. The surgery should be done by a doctor with more anal experience, so it is recommended that patients go to the hospital in time to get a clear diagnosis and then take the appropriate surgical treatment.