To enhance the efficacy of an inactivated vaccine against pseudorabies virus (PRV), we evaluated the adjuvant properties of Fc domain of IgG. A cell line expressing mouse IgG Fc chimera on its surface was established. We found that when PRV was propagated in the cells expressing the Fc chimera, PRV virion incorporated the Fc. Immunization of BALB/c mice with inactivated PRV harboring Fc, which had been propagated in the cells expressing Fc on its surface, induced higher antibody production against PRV and protected mice more effectively from lethal challenge of virulent strain, comparing to the immunization with normal inactivated virus. Virus harboring Fc has a great potential as a new inactivated vaccine.