Vaccinomics studies are aimed at deepening the information on protective immune pathways and the effects of pathogens on immunity, as well as defining conservation relations. The number and variety of omic technologies used in vaccine research have been increasing over time. However, the core approaches are genomic, transcriptomic, and proteomic, and are explained in detail in this chapter. The amount of data obtained from genomic, transcriptomic, and proteomic studies is increasing day by day. Therefore, using bioinformatics tools to obtain the most comprehensive information is important to achieve the most accurate result.