The recombinant PSMA DNA vaccine for active immunotherapy of prostate cancer was investigated. Two DNA vaccine recombinant plasmids, pcDNA3.1/PSMA and pcDNA3.1/hBD-2-PSMA, were constructed by inserting the hBD-2 gene and PSMA gene into an eukarytoic expression vector pcDNA3.1. Expression of the two recombinants was detected in transfected COS-7 cells and inoculated mouse muscular cells by RT-PCR and immunohistochemical method. When immunized with pcDNA3.1/PSMA and pcDNA3.1/hBD-2-PSMA, the immunized BALB/c mice acquired specific antibody and T cell response to PSMA. The quantity of the spleen lymphocytes and their CTL activity against PSMA gene transfected-BALB/3T3 cells significantly increased in the immunized mice, and the CTL activity of lymphocytes from pcDNA3.1/hBD-2-PSMA immunized mice was significantly higher than that of pcDNA3.1/PSMA immunized mice. This result suggests that pcDNA3.1/hBD-2-PSMA would probably be developed as a DNA vaccine for the immunotherapy of prostate cancer.