Perineal itching may be caused by vulvar sclerosing moss, contact dermatitis, ringworm and other diseases. 1. Vulvar sclerosing moss: the etiology of this disease is not clear, it may be related to autoimmune abnormality, heredity, cell proliferation, pathogenic microbial infections, hormone level abnormality and other reasons. Patients will have symptoms such as vulvar itching, perianal itching and painful intercourse. 2. Contact dermatitis: this disease is due to skin contact with exogenous substances, stimulation of the skin caused by allergic reactions. Therefore, perianal and perineal itching may be caused by allergy to the material of underwear, detergents, condoms, sanitary napkins and so on. The patient’s perianal and perineal areas will also experience burning, swelling and pain. 3. Ringworm: The change is mainly caused by the infection of dermatophytes, which is common in the red trichophyton, and can also be transmitted with direct contact or indirect contact. The patient’s groin, perineum, perianal and buttocks and other places will appear itching, erythema and other symptoms. In addition to this, there can be two types of diseases at the same time, one is perianal itching caused by diseases such as hemorrhoids and chronic anal fissures. The other is perineal itching caused by gynecological diseases such as bacterial vaginitis and trichomoniasis. It is recommended that patients with perineal itching go to the hospital to improve the relevant examinations to clarify the specific causes.