Patients with anal swelling for two months may be caused by hemorrhoids, rectal prolapse, perianal abscess and other diseases. 1. hemorrhoids: hemorrhoids is a relatively common anorectal disease, its main manifestation of blood in the stool, hemorrhoidal prolapse, anal itching, anal swelling, anal moisture, etc., the patient appeared in the case of anal swelling may be caused by hemorrhoids. 2. Rectal prolapse: Rectal prolapse refers to the downward displacement of part or all of the rectal wall, which is manifested by the prolapse of rectal mucosa from the anus, and the patient may have incomplete defecation, anal falling sensation, anal incontinence, etc. Rectal prolapse may cause anal swelling. 3. Perianal abscess: perianal abscess, also known as perianal abscess, is an acute purulent infection that occurs in the soft tissues around the rectum and anus, or in the interstitial space around the rectum and anus to form an abscess, the patient may have a small lump in the anus, sudden severe pain, anus, rectum, a feeling of falling and swelling, accompanied by fever, chills and other symptoms. In addition, severe constipation, rectal polyps, anal canal inflammation and other diseases may also cause anal swelling for up to two months. It is recommended that the patient consult a doctor for examination to identify the cause of the disease and then carry out targeted treatment in order to avoid delaying the condition.