The skin microbiome plays a critical role in maintaining skin health and preventing inflammatory skin diseases (ISDs). The skin hosts a diverse microbiota, including bacteria, fungi, and viruses, which contribute to immune regulation and barrier function. Dysregulation of the skin microbiota is implicated in the pathogenesis of ISDs such as psoriasis, atopic dermatitis (AD), seborrheic dermatitis (SD), rosacea, acne, diaper dermatitis (DD), and Malassezia folliculitis (MF). The skin microbiota undergoes changes in composition and function that can compromise the skin microbial barrier, leading to water loss, abnormal lipid metabolism, and the onset of ISDs. Microorganisms such as Staphylococcus aureus release toxins that impair skin barrier function and allow entry into the bloodstream, triggering immune disorders and subsequent skin inflammation. Malassezia stimulates dendritic cells to release pro-inflammatory mediators, contributing to the development of ISDs. The skin microbiome is influenced by factors such as age, body site, and gender, with distinct microbial communities in different skin regions. The human skin microbiome is diverse, with 90% of individuals harboring a "core" symbiotic microbial community. The skin microbiome interacts with the immune system, influencing local and systemic immunity. Understanding the characteristics of the skin microbiome is essential for comprehending the development and treatment of ISDs. This review aims to systematically review microbial alterations and immune dysregulation in common ISDs, including psoriasis, rosacea, AD, SD, DD, and Malassezia folliculitis. It also explores the relationship between the composition/function of the human microbiome and the underlying mechanisms of skin diseases, providing new insights for clinical diagnosis and treatment. The skin microbiome is crucial for maintaining skin homeostasis and preventing disease. The review highlights the role of the skin microbiome in the pathogenesis of ISDs, emphasizing the importance of understanding microbial alterations and immune dysregulation in these conditions. The skin microbiome is a complex and evolving community that plays a vital role in maintaining skin health and preventing disease. The review provides new insights into the role of the human skin microbiota in ISDs, paving the way for future skin microbiome-specific targeted therapies.The skin microbiome plays a critical role in maintaining skin health and preventing inflammatory skin diseases (ISDs). The skin hosts a diverse microbiota, including bacteria, fungi, and viruses, which contribute to immune regulation and barrier function. Dysregulation of the skin microbiota is implicated in the pathogenesis of ISDs such as psoriasis, atopic dermatitis (AD), seborrheic dermatitis (SD), rosacea, acne, diaper dermatitis (DD), and Malassezia folliculitis (MF). The skin microbiota undergoes changes in composition and function that can compromise the skin microbial barrier, leading to water loss, abnormal lipid metabolism, and the onset of ISDs. Microorganisms such as Staphylococcus aureus release toxins that impair skin barrier function and allow entry into the bloodstream, triggering immune disorders and subsequent skin inflammation. Malassezia stimulates dendritic cells to release pro-inflammatory mediators, contributing to the development of ISDs. The skin microbiome is influenced by factors such as age, body site, and gender, with distinct microbial communities in different skin regions. The human skin microbiome is diverse, with 90% of individuals harboring a "core" symbiotic microbial community. The skin microbiome interacts with the immune system, influencing local and systemic immunity. Understanding the characteristics of the skin microbiome is essential for comprehending the development and treatment of ISDs. This review aims to systematically review microbial alterations and immune dysregulation in common ISDs, including psoriasis, rosacea, AD, SD, DD, and Malassezia folliculitis. It also explores the relationship between the composition/function of the human microbiome and the underlying mechanisms of skin diseases, providing new insights for clinical diagnosis and treatment. The skin microbiome is crucial for maintaining skin homeostasis and preventing disease. The review highlights the role of the skin microbiome in the pathogenesis of ISDs, emphasizing the importance of understanding microbial alterations and immune dysregulation in these conditions. The skin microbiome is a complex and evolving community that plays a vital role in maintaining skin health and preventing disease. The review provides new insights into the role of the human skin microbiota in ISDs, paving the way for future skin microbiome-specific targeted therapies.