Lupus erythematosus is an autoimmune disease that invades the skin or various organs, which varies in severity clinically and is generally divided into cutaneous lupus erythematosus and systemic lupus erythematosus. Its etiology is complex and is considered to be an autoimmune disease related to genetic qualities under the role of multiple factors, as follows: i. genetic factors, there may be similar patients in the family; ii. immunological abnormalities, mainly characterized by T-cell The level of sex hormones, lupus patients tend to occur in women of childbearing age, and pregnancy and oral contraceptives can aggravate the disease, which suggests that lupus erythematosus is related to the level of estrogen; iv. environmental factors, mainly ultraviolet light, sun exposure is one of the factors that cause the aggravation of lupus; v. drugs, certain drugs can cause lupus erythematosus, such as procainamide, hydrazinepyridazine Sixth, infection factors, a variety of infectious factors can lead to lymphocyte mechanization triggering lupus activity, especially viral infection. Therefore, the causes of lupus erythematosus are complex, and it is generally believed that it is an autoimmune disease caused by immune dysfunction on the basis of genetic defects and the production of autoantibodies under the effect of ultraviolet light, infection, drugs or other factors.