The present invention provides a PRRSV subunit vaccine comprising a fusion protein having neutralization titers evoked, PE-PQGAB-K3, which comprises a chimeric polypeptide containing N-terminal portions of PRRSV ORF5 and ORF6 structure proteins a portion of Pseudomonas exotoxin A binding and translocation domain and a carboxyl terminal domain containing KDEL-KDEL-KDEL(K3) sequence. Less inflammation of PE-PQGAB-K3 vaccine group in their lungs post being PRRSV-challenged indicates that PQGAB without an antigen-specific allergy effect. Importantly, PE-PQGAB-K3 vaccine presents a good protection against PRRSV infection than control groups in pig challenged experiment.
