The present invention is to provide a kind of avian infectious bursal disease virus of the saltant type through rite-directed mutagenesis generation (IBDV) VP2 protein, is particularly to provide three kinds of VP2-441 variants (variants): H249A, H253A and H249.253A. The present invention further provides what IBDV inspection of the saltant types VP2 protein such as this and the purposes of vaccine.本發明為提供一種經定點突變產生之突變型雞傳染性華氏囊病病毒(IBDV)VP2蛋白質,特別地係提供三種VP2-441變體(variants):H249A、H253A及H249.253A。本發明進一步提供該等突變型VP2蛋白質用於IBDV檢驗及疫苗之用途。