Partial immunoactivities of peptidoglycan(PG)isolated from lactic acid bacteria were investigated.PG isolated from strain Z8 and Z17 of lactic acid bacteria respectively,had similar immunoactivities.The phagocytic function of MΦ(macrophage)increased markedly and serum lysozyme activity was significantly enhanced by injection of PG-extracts on mice.Investigation of immuno-enhancing effects of PG on vaccine of Newcastle disease in chickens showed that the hemagglutination inhibition levels of PG were higher than that of the control and the level was maintained for a longer time as compared to the control.