The difference between SLE and urticaria lies in the following aspects: First, in terms of etiology, SLE is an autoimmune disease, mainly caused by autoantibodies that can destroy the skin and internal organ system, while urticaria is mainly due to hypersensitivity reactions caused by allergens produced by the self. Secondly, the rash manifestation, systemic lupus erythematosus can appear as butterfly erythema and annular erythema, while urticaria appears as a fading, fading, scarless wind mass, and is accompanied by a positive skin scratching sign; thirdly, in clinical treatment, glucocorticoid medication is preferred for systemic lupus erythematosus, such as prednisone acetate tablets, while urticaria is mainly treated by antihistamines, such as levocetirizine hydrochloride oral solution.