Abstract: Epithelial cells of the lungs secrete inflammatory mediators to activate resident immune cells in the airway for immune protection after stimulation, including innate lymphoid cells. Although the number of innate lymphoid cells is less, they can secrete numerous cytokines involving in immune response. Type 3 innate lymphoid cells (ILC3) are important subtype of innate lymphoid cells. ILC3 and its secreted cytokines interleukin (IL)-17 and IL-22 play immune defense roles in clearing pathogens, promoting mucosal repair and maintaining mucosal barrier homeostasis in respiratory infections. In this review, the development and activation mechanisms of ILC3 and its roles in pediatric airway inflammatory diseases, and latest research progress were summarized.