The present invention provides an antigen chimera, comprising: a fusion protein for an antigen and a mucosal immune adjuvant protein monomer that can form a polymer, and the mucosal immune adjuvant protein monomer that can form a polymer. The mucosal immune adjuvant protein monomer that can form a polymer is one selected from a cholera toxin B subunit (CTB) and Escherichia coli Heat-labile Enterotoxin B subunit (LTB), the polymer is a pentamer, and a mole ratio of the fusion protein to the mucosal immune adjuvant protein monomer that can form a polymer in the chimera is 1:4. In the present invention, a characteristic that a mucosal immune adjuvant protein can form a pentamer is used to form a chimeric structure, so as to form an antigen having a higher titer. Moreover, a mucosal immune adjuvant protein is used to improve an immune effect, so as to improve an effect of enhancing antigen immunogenicity. In addition, a chimeric protein antigen formed of a recombined antigen of the present invention stimulates a mucous membrane to produce secrectory IgA and induce production of mucosal immunity.
