Abstract: The antibacterial activity of Ricinus communis leaf was studied for its in vitro antimicrobial activities through the disc diffusion method. The leaf extract of the castor plant significantly inhibited the growth of Bacillus cereus ATCC 14579, Bacillus cereus ATCC 10987, Bacillus cereus 10876, Escherichia coli 43889, Escherichia coli 35150 and Escherichia coli 43890. Various types of zone of inhibition were found against the selected bacteria using the R. communis leaf extract with three selected solvents. Methanolic extract showed the highest zone of inhibition (2.00 cm) against E. coli ATCC 43890 and minimum (1.33 cm) against B. cereus ATCC 14579. In case of petroleum ether and control, no zone of inhibition was found. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the methanolic extract ranged from (62.5-125 μg mL-1). In cell viability assay, methanolic extract completely inhibited the bacterial growth after 200 min expusure. The results of the present study suggest that R. communis can be used in food industry to control different food borne diseases.