Abstract: Based on the 16S rRNA sequence in GenBank for Ornithobacterium rhinotracheale(ORT),a pair of primers was selected for the amplification of the 671 bp fragment to establish a PCR method for ORT detection.This method could amplify the specific fragment in the reference strains,but not in chicken E.coli,Haemophilus paragallinarum,Salmonella Pullorum and Avian pasteurella multocida,of ORT.A sensitivity test indicated that the assay's lowest detection limit was 90 pg DNA.The PCR methodology appeared to be highly sensitive and specific for the purpose.Positive results were obtained on two isolated strains by using this newly developed PCR method.