The effectiveness of ozonated water in lowering Escherichia coli O157:H7 contamination on tomato surfaces is assessed in this study. Despite their nutritious value, tomatoes can become contaminated by pathogens during handling and processing.For different exposure durations (3, 6, 9, 12, and 15 minutes), tomatoes were inoculated with E. coli O157:H7 and treated with ozonated water at a concentration of 0.5 mg/L. The viable plate count method was used to determine the number of bacteria.The results showed that E. coli O157:H7 populations significantly decreased over time, with the largest drop at 15 minutes after treatment. Ozone's short halflife (around 20 minutes) and instability in water further restrict its longterm antibacterial effectiveness.Physical barriers on the tomato surface limit the effectiveness of ozonated water, even though it was found to be beneficial in lowering surface contamination when compared to untreated controls.According to these findings, ozonated water is a promising chemicalfree substitute for decontaminating produce; however, in order to improve microbial safety and stop regrowth during storage, delivery methods should be optimized and combined with other preservation strategies (such as cold storage or edible coatings).Ozone's potential as a nonthermal food safety intervention in the preparation of fresh produce is supported by this study. ........................ Key words:...............Ozone , Food safety, Tomatoes, Ozonated water, E. coli O157.