Objective:Through exploring the effect of L-theanine on the regulation of innate immune function in rats,this paper lays a foundation for the development of new food additives based on L-theanine as the main component.Methods:The effects of L-theanine treatment on immune organ index,immunoglobulin,lymphocyte proliferation and cytokine secretion in blood of rats are studied by comparing the factors among different groups.Results:L-theanine increases immunoglobulin G(IgG)secretion by promoting spleen development;promote intrinsic lymphocytes 1(ILC1)and lymphoid tissue induces cells(LTi)proliferation,promote interleukin-4(IL-4)secretion.Conclusion:L-theanine treatment can enhance the innate immune function in rats,and provide basis for the development and application of L-theanine as the main component of new food additive.