The present invention relates to a method for inhibiting, improving, or preventing aging, comprising administering to a subject in need thereof a composition comprising a recombinant protein of flagellin, which is the constituent of Vibrio vulnificus flagella, fused with a pathogenic protein antigen, which is pneumococcal surface protein A (PsaA) of Streptococcus pneumonia. 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.