The present invention discloses a T-cell immune response inhibitor. The T-cell immune response inhibitor supplied in the present invention comprises a targeted pathogen nucleic acid vaccine and said nucleic acid vaccine's expression protein antigen; or it comprises a targeted pathogen nucleic acid vaccine and said nucleic acid vaccine expression protein antigen's active polypeptide; or it comprises the inactivated pathogen and targeted pathogen nucleic acid vaccine. The T-cell immune response inhibitor in the present invention is able to stimulate the organism to produce the normal specific antibody immune response and to suppress a specific cell's immune response, in particular the Th1 immune response, thus it may be effectively applied to treatment of autoimmune diseases, organ transplants, allergies and control of T-cell levels.