Abstract: To express multi-epitope antigen of infectious bursal disease virus（IBDV）and analyze its immune characteristics, the multi-epitope recombinant gene resulting from VP2 and VP3 sequences was designed and amplified by PCR synthetic technology, and was cloned into pBVIL1 plasmid. The multi-epitope antigen was expressed by temperature induction at 42℃ with fusion and its immune reactivity was detected by IBDV standard antiserum, and the immunogenicity was evaluated using the titre of antiserum from mice. The results showed that multi-epitope fusion antigen was expressed with 31 kD molecular weight, its immune reactivity was confirmed using standard antisera through western blot assay and the antiserum titer was 1∶6 400 with ELISA method after mice immunization. It was concluded that the prokaryotic expression vector was constructed successfully and the multi-epitope antigen possessed the IBDV antigenic properties, which could be provided for pathogen diagnosis and genetic engineering vaccine research.