Abstract: In order to establish the detection of Hemagglutinating Encephalomyelitis Virus (HEV) by RT- PCR, a pair of oligonucleotide primers appropriate for PCR amplication was selected based on the HE gene and S gene of HEV. A reverse transcription–polymerase chain reaction (RT-PCR) assay was developed for the detection of HEV after optimization of the reaction conditions. The RT-PCR was sensitive and specific for HEV and did not amplify closely related bovine coronavirus and pseudorabies virus of pigs. The HEV can be found in many organs, especially found regularly in brain. So the brain of suspected pig is the best sample to detect