Xue-Er Zhang,1 Pai Zheng,1 Sheng-Zhen Ye,1,2 Xiao Ma,3 E Liu,1 Yao-Bin Pang,1 Qing-Ying He,1 Yu-Xiao Zhang,1 Wen-Quan Li,1 Jin-Hao Zeng,4 Jing Guo2 1Chengdu University of Traditional Chinese Medicine, Chengdu, 6610075, People’s Republic of China; 2Department of Dermatology, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, 6610072, People’s Republic of China; 3State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, People’s Republic of China; 4TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, 610072, People’s Republic of ChinaCorrespondence: Jing Guo, Department of Dermatology, Hospital of Chengdu University of Traditional Chinese Medicine, No. 39 Shi-er-qiao Road, 610072, Chengdu, Sichuan Province, 6610072, People’s Republic of China, Tel + 86 18980880167, Email Guojing66@cdutcm.edu.cn Jin-Hao Zeng, TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province, Hospital of Chengdu University of Traditional Chinese Medicine, No. 39 Shi-er-qiao Road, 610072, Chengdu, Sichuan Province, 6610072, People’s Republic of China, Tel + 86 15999931573, Email zengjinhao@cdutcm.edu.cnAbstract: As the body’s largest organ, the skin harbors a highly diverse microbiota, playing a crucial role in resisting foreign pathogens, nurturing the immune system, and metabolizing natural products. The dysregulation of human skin microbiota is implicated in immune dysregulation and inflammatory responses. This review delineates the microbial alterations and immune dysregulation features in common Inflammatory Skin Diseases (ISDs) such as psoriasis, rosacea, atopic dermatitis(AD), seborrheic dermatitis(SD), diaper dermatitis(DD), and Malassezia folliculitis(MF).The skin microbiota, a complex and evolving community, undergoes changes in composition and function that can compromise the skin microbial barrier. These alterations induce water loss and abnormal lipid metabolism, contributing to the onset of ISDs. Additionally, microorganisms release toxins, like Staphylococcus aureus secreted α toxins and proteases, which may dissolve the stratum corneum, impairing skin barrier function and allowing entry into the bloodstream. Microbes entering the bloodstream activate molecular signals, leading to immune disorders and subsequent skin inflammatory responses. For instance, Malassezia stimulates dendritic cells(DCs) to release IL-12 and IL-23, differentiating into a Th17 cell population and producing proinflammatory mediators such as IL-17, IL-22, TNF-α, and IFN-α.This review offers new insights into the role of the human skin microbiota in ISDs, paving the way for future skin microbiome-specific targeted therapies.Keywords: skin microbiota, inflammatory skin diseases, atopic dermatitis, seborrheic dermatitis, rosacea, acne, psoriasis, diaper dermatitis, Malassezia folliculitis