There is no essential difference between eczema in children and eczema in adults in terms of the underlying pathogenesis. In general, they are a variety of internal and external factors acting together on susceptible individuals with a genetic background to cause a type of non-infectious skin inflammation, but due to differences in life stages and physiological structure, the internal and external factors that induce the occurrence of eczema in children and adults are different. Internal factors, in childhood, because growth and development have not yet been completed, chronic systemic diseases are also relatively rare, the internal causes of eczema in children are dominated by genetic factors, followed by the relative weakness of the skin mucosal barrier, susceptible to bacterial, viral and parasitic infections. As for external factors, children with eczema generally do not have occupational exposure triggers, but ingestion triggers such as eating fish, shrimp, beef and mutton, and inhalation triggers such as pollen and dust mites play a more important role in the development of eczema. In addition, “eczema” that extends from the neonatal period to childhood should be diagnosed as “atopic dermatitis”. It is a chronic inflammatory skin disease associated with genetic allergies, with no significant gender differences in its onset. The lesions are polymorphic and may have a tendency to ooze similar to acute eczema, with initial onset between 2 months and 1 year of age. The disease is usually in remission within 2 years of age. After 1-2 years of remission, the disease worsens again after entering childhood, and some of it may extend into adolescence and adulthood. It is a chronic inflammatory skin disease that is mediated by the immune system through the interaction of genetic and environmental factors.