The present invention relates to an antigen composition for preventing or treating viral infectious diseases, comprising, as an active ingredient, a multiple variant protein of a recombinant hemagglutinin monomeric protein in an influenza virus. In addition, the present invention relates to an antigen composition for preventing or treating viral infectious diseases, comprising a scaffold-based fusion protein. The antigen composition for preventing or treating viral infectious diseases, according to the present invention, has an outstanding preventive effect of inhibiting the proliferation and replication of viruses having various mutations, and is recyclable and safe by means of using a recombinant protein, and thus can be widely used in various industrial fields, such as the medicine and life science fields.