To investigate the enhancement of Lagurus lagurus zona pellucida 3 gene (lzp3) immunization induced by molecular adjuvant C3d in comparison with plasmid pcDNA3-LZP3 (pcD-L) in non-C3d fused form, the eukaryotic expression vector pcDNA3-LZP3-C3d3 (pcD-LC) including lzp3 and three copies of C3d in fusion form was constructed. In vitro,RT-PCR and Western blot showed that lzp3 mRNA and protein were expressed in HeLa cells transfected with pcD-L and pcD-LC, respectively. In vivo,the result of ELISA showed that NIH female mice vaccined with pcD-LC elicited higher titer, longer lasting anti-LZP3 antibody than non-C3d fused form pcD-L (P<0.05) by intramuscular gene immunization. MTT analysis indicated that the lymphocytes proliferation response of the pcD-LC primed mice was significantly stronger than that of the blank plasmid injected mice. Antifertility experiment showed that pcD-LC had enhanced effect on blocking fertility of mice (P<0.05) with no disruption of follicular development. These results proved that C3d enhanced immune responses induced by lzp3 vaccine and antifertility effect,and provided the basis for the future study of the Lagurus lagurus reproductive controlling.