The present invention relates to a universal H5N1 vaccine. More specifically, the present invention relates to the identification of three H5N1 strains which cover the entire variants in the neutralizing epitopes of hemagglutinin among most H5N1 lineages. The present invention further relates a universal H5N1 vaccine that comprises the three H5N1 strains or that comprises hemagglutinin peptides of each of these three strains.