Abstract: Immune function of Morinda citrigolia fruit powder was evaluated in this study through animal feeding test.The mice were feed with Morinda citrigolia fruit powder with 3 dose groups ( 0.833, 1.667, 2.500 g/kg·BW) for 30 days. And then subjected to body weight, organ/body weight ratio, lymphocyte transformation test, serum hemolysin determination, mice carbon clearance test, mouse peritoneal macrophage phagocytosis test and NK cell activity assay. The results indicated that both the swelling degree of toes of middle dose group and high dose group were significant higher than the blank control group ( p <0.05) , cellular immunity function test result was positive. Both the number of plaque forming cells of middle dose group and high dose group were significantly increased ( p < 0.05) , humoral immunity function test result was positive. The conclusion is that the Morinda citrigolia fruit powder had the function of enhancing immunity.