A significant association between tomato consumption and a lower risk of developing hypertension has been reported. In this study, we aimed to investigate the relationship between tomato intake and prehypertension risk among Korean adults. Hypertension was defined according to the criteria established by the Korean Society of Hypertension. The study participants were selected from the Health Examinees cohort study. Tomato consumption was measured using a food frequency questionnaire and categorized into quintiles based on the amount consumed. Higher tomato consumption was associated with a lower risk of prehypertension in men (hazard ratio 0.86, 95% confidence interval 0.80–0.92, p for trend 0.0005). Women in the highest quintile also showed a similar trend (hazard ratio 0.94, 95% confidence interval 0.90–0.99, p for trend 0.0091). Stratified analyses revealed a reduced risk of prehypertension across all subgroups, except underweight individuals and those with a history of alcohol consumption (all P-interaction <0.05). These findings indicate that higher tomato intake may offer potential advantages for managing blood pressure levels.