In the increasing crisis of pandemic of infectious diseases all over the world in recent years, it is the most necessary to develop readily available vaccines even in developing countries. Since many pathogens establish their initial infections through the mucosal surface in our bodies, the induction of mucosal immune responses by vaccines are thought to be important for the prevention of infectious diseases through mucosal site. Oral administration of vaccines has abilities to elicit mucosal immune responses at mucosal tissues with various advantages such as easy skill for administration, less stressful for vaccine recipients and safer than systemic injection. Here, we show our novel strategies for inducing mucosal immune responses by oral vaccine administration.