Background: Fast-food consumption among children and adolescents is a growing global health concern due to changing dietary habits and lifestyles. The study aimed to examine the relationship among attitude, subjective norms, perceived behavioral control and intention to fast-food consumption among high school students in Bangladesh. Methods: A correlational design using the Theory of Planned Behavior assessed attitudes, subjective norms, and perceived behavioral control in relation to fast-food consumption intention. Data were analyzed using descriptive statistics, independent t-test, one-way ANOVA, and Pearson's correlation coefficient. Results: Using the Theory of Planned Behavior, the study found that Attitude (r=.487, p<.001), subjective norm (r=.177, p<.05), and perceived behavioral control (r=.594, p<.001) were significantly positively correlated with students' intention toward fast-food consumption. Conclusion: Improved nursing practices and policymaker strategies can support effective health education to change adolescents’ and families’ attitudes toward fast food consumption. The study’s findings may guide government and private sectors in appointing child health nurses in schools and colleges.