The causes of anal pain and a little blood are as follows: 1, anal fissure: the process of defecation will stimulate the anal sphincter, resulting in anal sphincter spasm, resulting in pain and bleeding, must go to the hospital to receive regular treatment; 2, perianal eczema: due to perianal eczema leads to anal dampness, itching, the emergence of inflammatory secretions stimulation, so it will lead to anal pain and bleeding, need to go to the hospital for formal guidance Treatment; 3. perianal abscess, anal fistula: sometimes pain and bleeding can also occur, but the bleeding is mainly pus and blood, so it is necessary to identify and receive regular guidance and treatment at the hospital if you cannot be sure; 4. hemorrhoids: in case of inflammatory external hemorrhoids, thrombosed external hemorrhoids or mixed hemorrhoids, prolapse and impaction can also lead to pain and bleeding.