As the first line of defense, innate immunity plays an important role in the defense of pathogens.ILC2s, a subset of innate lymphoid cells(ILCs)which is an important effector cell in the innate immune system, can produce a large number of type 2 cytokines and some tissue growth factors.ILC2s widely exist in various tissues of the body, of which lung mucosa is the main habitat.ILC2s are involved in lung development and may also be involved in lung injury and tissue repair induced by various factors.Further study of ILC2s will provide new insights into the mechanism of lung development and lung injury.