This review summarizes and discusses a new vaccine strategy based on xenogeneic homologous molecules by the breaking of immune tolerance against the growth factors or their receptors associated with tumor growth in a cross-reaction between the xenogeneic homologs and self-molecules. The xenogeneic vaccine may circumvent the fact that few tumor-specific antigens have been identified in human solid tumors and that the host usually shows immune tolerance to self-molecules as antigens. It may be of importance for the further exploration of the applications of xenogeneic homologous genes identified in human and other animal genome sequence projects in cancer therapy.