A combined inactivated Bovine Rota and Corona viruses vaccine was prepared on Madin Darby Bovine Kidney (MDBK), by use of Binary Ethyleneimine (BEI), as an inactivant. Evaluation of the vaccine for its safety and potency was conducted through study in laboratory animals and calves. The prepared vaccine proved potent as the developed antibodies for Bovine Rota Virus (BRV) and Bovine Corona Virus (BCV) appeared as early as 10 days post vaccination (PV), and reached its peak at the 35th day PV and remained high till the end of the 2nd month. The developed specific antibodies were quantitively measured by both Serum Neutralization Test (SNT) and ELISA technique.