The causes of psoriasis include genetic factors, infectious factors, such as viral infections and bacterial infections, which can promote the occurrence of psoriasis. Endocrine metabolic abnormalities in the body, psychoneurological conditions, and immune factors can also cause the occurrence of psoriasis. Psoriasis is an immune-mediated chronic inflammatory skin disease, which is divided into common psoriasis, pustular psoriasis, arthritic psoriasis and erythrodermic psoriasis according to its manifestation. The pattern is dotted or dripping, map-like, coin-like, ring-like, and even seborrheic dermatitis-like performance on the scalp.