Gene vaccines have proven to be a powerful tool to induce anti-allergic immune responses. Their underlying functional principle is based on the recruitment of allergen-specific Th1 cells and the establishment of a Th1 cytokine milieu, which protects against the development of a Th2-biased response and balances an already ongoing Th2-type response. Genetic immunization also offers novel approaches to the major problems associated with protein immunization, such as crosslinking of preexisting IgE on mast cells/basophils or induction of de novo synthesis of IgE by the protein immunization itself. In addition to the description of the principles of gene vaccination, this review gives a short overview of recently developed anti-allergic gene vaccines with an optimized efficacy and safety profile.