Seborrheic dermatitis is a chronic superficial inflammatory skin disease that occurs at the site of seborrhea. 1, Chinese medicine etiology pathogenesis This disease is due to the vegetative dampness and heat within the body, feel the wind evil. The wind-heat evil attacked outside, depressed for a long time to consume Yin and blood, Yin injury and blood dry; or plain blood dry body, and feel the wind-heat evil, blood deficiency wind, wind-heat dry evil contained in the skin, the skin is not moistened; or due to eating fatty, greasy, spicy products, so that the spleen and stomach transport abnormal, damp heat, damp heat contained in the skin and born. 2.Western medicine etiology and pathogenesis The cause of this disease is not yet fully understood, but it is mainly a secondary inflammation of the skin caused by seborrhea. It is presumed to be caused by changes in the composition of sebum, a significant increase in epidermal lipids and a decrease in free fat, and a disturbance in the skin flora in the epidermal area, such as the massive growth and reproduction of oval spores of furfur, which invade the skin; in addition, a large increase in sebum, through the role of non-pathogenic microorganisms originally present on the skin, such as Propionibacterium acnes, decompose free fatty acids and stimulate the skin to cause inflammation. In addition, genetic factors, mental factors, dietary habits, B vitamin deficiency, and alcoholism may have some influence on the development of the disease. 3, prevention and conditioning (1) should be light diet, eat more fruits, vegetables, avoid sugar, fat diet, avoid drinking alcohol and eating spicy and other stimulating food. (2) Avoid scratching and washing with irritating soap. (3) Attention should be paid to a regular life, maintain sufficient sleep, and keep the bowels open.