An oily and itchy scalp is considered to be seborrheic dermatitis. The cause of the disease is not yet clear, and may be related to Malassezia colonization, increased lipids, impaired skin barrier function, and other factors. 1. Malassezia colonization: Malassezia colonization of scalp hair follicles, if growth and reproduction will stimulate the hair follicle causing increased secretion. 2. Increased lipids: increased follicular oily secretions can also lead to an oily, itchy scalp. 3. Impaired skin barrier function: the skin’s immune function barrier is impaired, will also affect the normal protective function of the scalp, which will lead to the scalp love oil very itchy. 4. Other factors: the immune response of the scalp, individual susceptibility, genetic factors, mental stress, eating spicy, drinking alcohol, etc., also belong to the triggering factors. Seborrheic dermatitis of the scalp, it is recommended to seek timely medical treatment, under the guidance of the doctor active treatment.