The following are some of the reasons why hemorrhoids are itchy: 1. When internal hemorrhoids occur, patients can cause the anal cushion attached to the anal canal wall to move down, resulting in the prolapse of the hemorrhoid nucleus, which repeatedly stimulates the perianal skin, causing perianal skin itching. The nucleus can also stimulate the perianal skin to secrete mucus, resulting in perianal dampness, which can lead to perianal eczema and further perianal itching. 2. Patients with external hemorrhoids can experience dampness, uncleanliness and itching in the perianal area due to varicose veins in the rectum. 3. 4. Individual patients may also have significant itching due to hemorrhoids accompanied by perianal infections such as parasitic and bacterial infections.