Psoriasis is a chronic inflammatory skin disease mediated by abnormal T-lymphocyte function as the main mechanism, and systemic therapy is a more desirable strategy in terms of the upstream aspects of pathogenesis. However, given the current problems of systemic western drug therapy, including varying degrees of adverse effects, it makes systemic western drug therapy mainly used for severe or intractable psoriasis. Therefore, topical topical treatment remains the most widely used first-line treatment for most mild to moderate patients. Based on evidence-based medical evidence, topical drug therapy for psoriasis can be administered with a variety of drugs and modalities such as single agents, combination agents, or combination therapy. Among the first-line therapeutic agents include: 1. Vitamin D3 derivatives: Calcitriol ointment is currently the main drug used as a control therapy and maintenance therapy in the treatment of chronic plaque psoriasis. Tacalcitol ointment can be used for facial and interscalene psoriasis; 2. Glucocorticoid preparations: used alone, short-term for punctate and plaque psoriasis and can be changed to vitamin D3 derivatives for maintenance therapy after control; 3. Calcipotriol betamethasone ointment: evidence-based medicine confirms that this combination has a rapid onset of action and can be used for long-term maintenance therapy after about one month of control; 4. Vitamin A acid 5. Enlin preparations: For chronic plaque psoriasis, they are used in the control phase of treatment; 6. Keratin-enabling drugs: Various tar preparations, 3％ salicylic acid, etc. are used for various types and different stages of psoriasis lesions; 7. stages of psoriasis, which can be used alone or in combination with other drugs, and have become the basic treatment of psoriasis; in addition, some other topical preparations, such as 0.05% azelaic acid hydrochloride solution and 10% hippuric acid ointment, can also be used for the control treatment of intractable chronic plaque psoriasis. In addition to the above drug types, some safe and effective treatment modalities, such as control therapy, maintenance therapy and sequential therapy, need to be promoted. These modalities can improve the efficacy, shorten the course of treatment, improve patient compliance, reduce relapse, etc. In addition to topical treatment alone, topical treatment is often used in combination with ultraviolet therapy and systemic therapy.