The most frequent cause of bovine respiratory illness in the world is respiratory syncytial virus (BRSV) of cattle. The objective of the present investigation was to detect the bovine respiratory syncytial virus (BRSV) utilizing nested RT-PCR and a mono-screen antigen-enzyme-immunosorbent assay (Antigen-ELISA). It also searched for to evaluate the success of the diagnostic techniques. A total of four hundred and fifty nasal swabs from suspected respiratory infection cattle of local breeds aged 1-4 years were obtained. Out of the Four hundred and fifty nasals wabs, 168(37.3%) samples were positive to BRSV using RT-PCR technique (P< 0.05), while 139 (30.8%) samples were positive to BRSV using direct ELISA. However, 29 (6.4%) animals were negative results for the direct ELISA test but positive results for the RT-PCR technique. Considering antigen ELISA as the gold standard, the sensitivity and specificity of RT-PCR technique were 82.70% and 97% respectively. Based on Kappa value was (0.838), a perfect agreement between the two diagnostic methods. In conclusion , the One Tube RT-PCR System Script RT-PCR Premix Kit had the best sensitivity, specificity, and agreement when compared to the mono screen Antigen enzyme-linked immunosorbent assay BRSV /Sandwich double well (Antigen -ELISA). This implies that BRSV infection is detected using both assays.Antigen-ELISA is a sensitive, inexpensive test that may be used for routine diagnosis.