Abstract: Atopic dermatitis (AD) is a common chronic hereditary atopic allergic skin disease of unclear origin.This article states the roles of environmental factors related to the initiation and progression of AD,such as living environment,pet exposure,and diets.Protective factors such as early breastfeeding,daily cleaning and intestinal flora,as well as risk factors such as infection,obesity,work in pregnancy,stress,and physical and chemical stimuli like cigarettes and drastic temperature changes,are also reviewed.