Coronavirus, particularly the genus Betacoronavirus, has been identified as a deadly source of numerous acute respiratory epidemics worldwide, affecting both humans and animals. The genus includes Covid-19, Severe acute respiratory syndrome coronavirus, and Middle East respiratory syndrome-related coronaviruses.In contrast, others are expected to have the risk of transformation such as bovine and porcine coronavirus. We screened a set of natural plant water extract which are red onion (Allium cepa), shallot (Allium ampeloprasum), watercress (Eruca sativa), and wormwood (Artemisia absinthium) that weighed and dissolved into a specific concentration then filtrated by specific biological filters. These extracts are known for their strong inhibition of the cytopathogenic effect of many pathogens. The cytotoxicity assay of the extracted plants was evaluated by the MTT assay using serial concentrations from the red onion and shallot extracts (10-100 ug) and wormwood and watercress extracts (20-200ug). The antiviral effect was evaluated using the concentrations mentioned above of the plants water extracts by application on the Madin Derby Bovine Kidney (MDBK) cell line infected with the virus. It showed pronounced inhibition of the bovine coronavirus (BCoV) in comparison to the control untreated cell line by both microscopic examination, and optical density index measurement. This work encourages the application of these extracts in trials of the treatment of the clinical cases of infected animals with coronavirus infection. It has the potential as a novel approach against coronavirus infections in animals.