Abstract: Waterfowl are the natural repository of avian influenza virus.To study the pathogenic molecular basis of highly pathogenic avian influenza from waterfow,8 recombinant PBD plasmids and rescued the recombinant virus were constructrd by reverse genetics techniques.The total RNA was extracted from the allantoic fluids of chick embryo with the infection of A/duck/HuBei/49/05 virus,PB2,PB1,PA,HA,NP,NA,M and NS were amplified by RT-PCR respectively,and they were cloned into PBD vector.Moreover,they also were transfected into 293 T cells.The result indicated that the recombinant virus was successfully rescued and named as R-DKHB.