The full-length P32 gene and the truncated P32 gene (MP-32) were amplified from the recombinant plasmid pMD-P32 by polymerase chain reaction (PCR) and cloned into pcDNA3. 1(+) and pcDNA3.1-CpG respectively. The recombinant plasmids (pcDNA3.1-P32, pcDNA3.1-CpG-P32 and pcDNA3. 1-CpG-MP32) were transfected into BHK-21 cells by using lipofectin. The expressed P32 protein was confirmed by indirect immunofluorescence assay (IFA). The BALB/c mice were immunized with these recombinant plasmids by intramuscular injection. The specific antibodies aginst CPV were detected by ELISA kit weekly. The murine splenic T lymphocyte subgroups CD4+ and CD8+ were detected by flow cytometry. Results showed that the P32 protein was expressed successfully in vitro. After 2 weeks post im munization, the specific IgG antibodies against CPV were detected in the vaccinated mice. The percentage of CD4+ /CD8+ T cells was significantly higher than that of the control. In conclusion, these constructed eukaryotic vectors could induce humoral and celluar immune responses in mice.