Abstract: The present invention relates to a novel lactobacillus fermentum ATG-V5 strain or a composition for enhancing immunity, comprising same. The Lactobacillus fermentum ATG-V5 strain of the present invention has no cytotoxicity, and has the effect of enhancing immunity, such as increasing the amounts of nitric oxide (NO), interleukin 6 (IL-6) and tumor necrosis factor (TNF) secretion and phagocytosis of macrophages, reducing the amount of interleukin 1? (IL-1?) secretion of macrophages, increasing the cell viability of splenocytes, and increasing the amount of antibodies and cytokines secretion in the blood, and thus the strain can be effectively used as a material for a composition and a health functional food for enhancing immunity, and the composition and health functional food can be effectively used in enhancing individual immune activity. In addition, a health functional food comprising the food composition is also effective in enhancing individual immune activity.