Itchy scalp may be caused by ringworm, seborrheic dermatitis of the scalp, contact dermatitis and other diseases. 1. Tinea capitis: itchy scalp may be caused by tinea capitis. If the scalp is infected with Trichophyton, Epidermophyton, etc., it is easy to induce ringworm of the scalp, resulting in patients with scalp itching, scaling and other symptoms. 2. scalp seborrheic dermatitis: scalp very itchy may be suffering from scalp seborrheic dermatitis caused by genetic factors, Malassezia infection, immune dysfunction and other factors, may induce scalp seborrheic dermatitis, so that the patient appears scalp itching, greasy scales and other symptoms. 3. Contact dermatitis: If the scalp is in contact with hair dyes, shampoos and other allergens, it is easy to induce contact dermatitis, so that the patient has an itchy scalp, pimples, crusts, blisters and other symptoms. There are many reasons for the itchy scalp, it is recommended that the patient to the hospital for relevant examinations, after a clear diagnosis under the guidance of the doctor standardized treatment.