Psoriasis is a common chronic inflammatory skin disease in clinic. It often has a family history, and it has certain heredity. Psoriasis is mainly manifested as skin erythema, papules, scales. After the scales on the surface are scraped off, membrane phenomenon and spotty bleeding can be seen. After the diagnosis of psoriasis, we should actively treat it. Although psoriasis can not be eradicated so far, through drug treatment, the patient's condition can be controlled in a stable state without affecting the patient's daily life and work. The first-line drug for psoriasis is methotrexate. In addition, we can also combine retinoic acid drugs for treatment. In terms of the choice of topical drugs, carbotrianol ointment, tacrolimus ointment or glucocorticoid ointment can be used for external application. The above scheme is only for reference. Please use the drug according to the drug description or the doctor's advice in a regular hospital.