The present invention relates to a composition for preventing, improving, or treating aging, wherein the composition comprises a recombinant protein of flagellin, which is the constituent of Vibrio vulnificus flagella, fused with a pathogenic protein antigen, as an active component. According to the present invention, the recombinant protein of the present invention can improve external and internal aging-related malfunctions and enhance immunity. Also, the composition of the present invention can easily perform immunization through mucosal administration.