Bovine coronavirus (BCoV) and group A bovine rotavirus (BRV) are two of major causes for neonatal calf diarrhea. In the present study, a one-step duplex RT-PCR was established to detect and differentiate BCoV and group A BRV from fecal samples. The sensitivity of this method for BCoV and group A BRV was 10 PFU/100 ฮผl and 1 PFU/100 ฮผl, respectively. Twenty-eight diarrhea fecal samples were detected with this method, the result showed that 2 samples were identified as co-infected with BCoV and group A BRV, 26 samples were group A BRV positive, and 2 samples were negative. It proved that this method is sensitive for clinical fecal samples and is worth applying to laboratory diagnosis for BCoV and group A BRV.