Chicken infectious bursal disease viruses (IBDV) were isolated and purified from infected bursa and then the viruses were used to extract genomic RNA.The cDNA first strand was synthesized by reverse transcription using IBDV genomic RNA as the template.A DNA fragment coding for the viral protein 5(VP5) of IBDV was amplified by PCR,which was ligated with pcDNA3.1(+) vector following restriction enzyme digestion.The ligates were transformed into XL1 blue and the recombinant plasmid pIBDV VP5 was screened and identified.The sequencing for VP5 gene and its sequence analysis were performed.