MicroRNAs (miRNAs) are small non-coding RNA molecules that regulate gene expression post-transcriptionally. This review summarizes the role of miRNAs in immune regulation, including their involvement in immune cell differentiation, anti-infective immune responses, immunodeficiencies, autoimmune diseases, anticancer immunity, and transplantation. miRNAs are key regulators of immune cell function, such as T-cells, NK cells, B-cells, macrophages, dendritic cells, neutrophils, and mast cells. They modulate immune responses by influencing signaling pathways, cell differentiation, and function. miRNAs also play a role in anti-infective immunity, including antiviral, antibacterial, antifungal, and antiparasitic responses. Dysregulation of miRNAs is associated with various diseases, including autoimmune disorders, cancer, and immunodeficiencies. miRNAs have significant clinical applications, such as serving as biomarkers for disease diagnosis, prognosis, and treatment response prediction. They are also potential therapeutic targets for modulating immune responses. miRNAs are involved in immunomodulation through pharmacological, biological, physical exercise, and nutritional interventions. Their role in personalized medicine is growing, with miRNA-based approaches offering new possibilities for targeted therapies and improved patient outcomes. The study highlights the importance of miRNAs in immune regulation and their potential for translational and clinical applications.MicroRNAs (miRNAs) are small non-coding RNA molecules that regulate gene expression post-transcriptionally. This review summarizes the role of miRNAs in immune regulation, including their involvement in immune cell differentiation, anti-infective immune responses, immunodeficiencies, autoimmune diseases, anticancer immunity, and transplantation. miRNAs are key regulators of immune cell function, such as T-cells, NK cells, B-cells, macrophages, dendritic cells, neutrophils, and mast cells. They modulate immune responses by influencing signaling pathways, cell differentiation, and function. miRNAs also play a role in anti-infective immunity, including antiviral, antibacterial, antifungal, and antiparasitic responses. Dysregulation of miRNAs is associated with various diseases, including autoimmune disorders, cancer, and immunodeficiencies. miRNAs have significant clinical applications, such as serving as biomarkers for disease diagnosis, prognosis, and treatment response prediction. They are also potential therapeutic targets for modulating immune responses. miRNAs are involved in immunomodulation through pharmacological, biological, physical exercise, and nutritional interventions. Their role in personalized medicine is growing, with miRNA-based approaches offering new possibilities for targeted therapies and improved patient outcomes. The study highlights the importance of miRNAs in immune regulation and their potential for translational and clinical applications.