The grafting degree, surface hydrophobicity, ultraviolet spectrum, fluorescence spectrum and sensitization of glycosylated ovalbumin modified by different hexoses were studied. The results showed that galactose-modified ovalbumin had the highest degree of glycosylation and the lowest fructose modification; the glycosylation reaction reduced the surface hydrophobicity of ovalbumin. UV and fluorescence conformational characterization showed that heat treatment during glycosylation, and the change of molecular group destroyed the original conformation of ovalbumin, with exposing the aromatic amino acid, and the highest degree of destruction of ovalbumin conformation by galactose. The glycosylation reduced the allergenicity of ovalbumin, while the binding capacity of fructose-modified ovalbumin IgG/IgE decreased slightly, which was much lower than that of galactose and glucose.