There is a big hard lump inside the perianal area and the bowel movement is smooth. Consider rectal-anal tube tumor, perianal abscess, rectal polyp, hemorrhoids and other causes. 1. Rectal-anal tube tumor such as anal papilloma, usually due to long-term chronic inflammation or chronic anal fissure caused by foreign body proliferation, thus touching is a hard lump, harder, not easy to push. When the lump is small and does not cause colonic obstruction, the bowel movement is smooth. 2. When the perianal hard lump is accompanied by obvious tenderness, serious systemic inflammatory reaction manifestations, such as fever, consider perianal abscess. The shape of the lump is regular due to pus encapsulation, and it is not easy to cause rectal obstruction, and the bowel movement is smooth. 3. Long-term chronic inflammation or abnormal bowel habits may also lead to rectal polyps, in addition to perianal lumps, usually no other symptoms, rare mucus stool. Polyps are usually many in number and small in size, and do not cause intestinal obstruction, and defecation is not obstructed. 4. Long-term spicy food or dry bowel movements can cause hemorrhoids, and repeated episodes can lead to perianal lumps. The lumps themselves do not affect bowel movements, but may cause difficulty in bowel movements due to hemorrhoids. The appearance of perianal hard lumps, it is recommended to go to the hospital in time for rectal diagnosis and other systematic examination, to clarify the cause of the disease, and give treatment as soon as possible, so as not to aggravate the deterioration of the condition.