The specific primers and Taqman probe were designed and synthesized according to the UL31 gene sequence available in GenBank(EF417996).The fragment is 76 bp.A Taq Real-time fluorescent quantitative PCR assay was established for detection of Duck Plague Virus DNA based on DNA copy obtained from attenuated vaccine strain as a positive template.The sensitivity of the test for DEV is 2.1 × 100-2.1 × 109 copies.The minimum detection limit is 2.1 copies(2.1 fg).Tissues,excrement and blood of 4 ducks challenged with DEV were detected repeatly 3 times by this method.All results were positive (3/3).The specificity of the assay was proven based on no amplification by detecting DNA from normal duck cells,duck viral hepatitis virus,Pasteurella,E.coli,S.gall inarum,Newcastle disease virus,goosling plague virus et ai.The whole process of the test could be completed within 4 hours.It brings about quantification detection of DEV DNA.