Abstract: On the basis of the theory "Lung combined with Gut, Gut connected to Skin" in Neijing, the "skin", "lung" and "gut" in close relationship constitutes the physiology and pathology triangle, the three will influence each other in their respective disease system.This theory has guiding significance for the theoretical research, clinical research and experimental research of external Chinese medicine. The modern research of "skin-lung-gut" axis is proposed to discuss the relationship between the three in terms of physical structure, immunity, endocrine, and nerves. In recent years, the skin microecology has received more and more attention. Based on the perspective of microbiome, this article explores the temporal and spatial correlation of "skin", "lung" and "gut" in the "atopic march" allergic diseases starting from atopic dermatitis. Regulation of skin microbiome based on "skin-lung-gut" axis provides not only a new perspective for the prevention and treatment of allergic diseases, but also new ideas for the mechanism research of external preparations of Chinese medicine.