In fission yeast (Schizosaccharomyces pombe), pac1 gene was cloned with 99.3% nucleotide sequence similarity with published pac1 in GenBank. In pET-5α expression system, the expression product of cloned pac1 in E. coli showed activity to degrade the double-strand RNA. Harboring the binary vector pBI121, which contains pac1 gene, Agrobacterium tumefaciens strain LBA4404 was used to transform the wheat immature embryos precultured 7―10 d. After preregeneration, regeneration and selection culture stage, totally 41 G418 resistant plants were obtained, in which 25 lines were proved to integrate with transgene and express transgene normally by PCR, Dot blot, RT-PCR and ELISA detection. Antivirus test carried out on 25 positive lines with high dose of Barley yellow dwarf virus-GPV revealed that 12 lines had resistance to BVDV-GPV in low level, another 12 lines had resistance to BVDV- GPV in middle level, and 1 line showed resistance to BVDV-GPV in high level. However, both low and middle level of resistance plants showed no symptoms when infected by viruses at low dose, which suggested the dose-dependent effect of the resistance mediated by pac1 to BYDV-GPV.