Bovine Rotavirus (BRV) is a major cause of neonatal calf diarrhea throughout the world. The successful effects of cefotaxime sodium (100 µg/ ml) on bovine rotavirus were studied. MDBK cells were treated with cefotaxime (CTAX) pre- or post-infection and the virus cytopathic effect was observed and virus proteins were analyzed by western blot technique. Also, the diarrheas were scored in BRV infected mice treated with CTAX. Results showed that the CTAX inhibited virus cytopathic effect on MDBK cells, and prevented virus induced diarrhea in experimentally infected mice. As revealed by western blot analysis of viral proteins expressed in CTAX pretreated MDBK cells, the effect of CTAX on BRV was related to the inhibition of synthesis of the VP3 and NSP2 rotavirus proteins, which are major components of the early replication intermediate of rotavirus. In conclusion, CTAX could be used as inhibitor of BRV replication