Atopic dermatitis, also known as “atopic dermatitis” and “genetic allergic dermatitis”, is a chronic inflammatory skin disease associated with genetic allergic qualities. It is characterized by pruritus, polymorphic lesions with a tendency to exude, and is often associated with asthma and allergic rhinitis. The etiology of atopic dermatitis is not fully understood and may be related to genetics and environment. The clinical manifestations are varied and can manifest as acute and chronic recurrent episodes. The disease has different clinical manifestations at different ages and can usually be divided into infancy, childhood, youth and adulthood. 1. Infancy: About 60% of patients develop the disease within 1 year of age, more after two months of birth. The initial lesions are pruritic erythema on the cheek and face, followed by the appearance of pinpoint-sized papules and papules on the basis of erythema, densely packed into patches, the lesions are polymorphic, the boundaries are unclear, scratching and rubbing soon after the formation of vesicles, oozing and crusting, and can quickly expand to other parts. The disease is sometimes severe and sometimes light. 2.Childhood: Most of the disease occurs in infancy after 1~2 years of remission and gradually worsens, and a few of them continue to occur since infancy. The lesions involve the flexors or extensors of the limbs, often limited to the elbow fossa and popliteal fossa, followed by the eyelids, face and neck. 3.Young adult stage: refers to the adolescent stage and adult stage of atopic dermatitis after the age of 12 years, which can develop from childhood or occur directly. It occurs in the elbow fossa, popliteal fossa, extremities, trunk, and palm stumbling area in some patients. Atopic dermatitis should be avoided by avoiding environmental factors that may aggravate it, reducing the number of baths and soaps used to avoid excessive removal of the sebaceous film, and topical moisturizers can be used with the advice of a physician.