Background: Excessive consumption of Sugar-Sweetened Beverages (SSBs) is a health problem in most societies today, which has adverse consequences in health, social and economic areas. The aim of this study was to investigate the effect of the application of social cognitive theory (SCT) in the design and evaluation of an educational intervention in order to adopt behaviors to prevent excessive consumption of SSBs in students. Methods: The current research was a quasi-experimental study. Using multistage sampling, 100 Junior High-school students in Urmia, Iran in 2021 were selected and assigned to two groups, namely intervention (n=100) and control (n=100). To collect the study data, the researchers utilized a researcher-made questionnaire including items about demographic information and SCT constructs such as awareness, outcome expectations, self-regulation, self-efficacy, social support, barriers and Preventive behaviors, which was completed in two stages before and three months after the last training session,the data were analyzed using the SPSS Software version 25. 0. Results: The mean age of the participants in the intervention and control groups was 13. 71 ±,0. 71 and 13. 84 ±,0. 81, respectively. Before the intervention, the mean scores of social cognitive theory structures and desired behavior were not significantly different between the two groups. But three months after the intervention, the mean scores of knowledge constructs, outcome expectations, self-regulation, self-efficacy, social support, perceived barriers, and desirable student behavior showed a significant difference between the two groups (P<0. 001). Conclusion: The results of the study revealed that social cognitive theory can be used as a theoretical basis for designing and evaluating interventions to encourage people to follow a proper diet and reduce the consumption of SSBs.