<p>In this study, social media addiction, which attracts the attention of researchers today and is a risk factor for adolescents, was examined as a predictor of subjective well-being, which is accepted as one of the dimensions of functionality for mental health, especially within the framework of a positive approach. While explaining this relationship, the variables of social self-efficacy and school engagement, which again contribute to the psycho-social development area of ​​adolescence as a supporter, were also included in the process as mediator variables. The sample of the study consists of 821 students studying in high schools. SPSS 27.0 program was used for the correlation analyses of the estimated model of the study, and PROCESS Macro (Model-6) was used for mediator analyses. As a result of the analyses, it was seen that level of social media addiction was negatively and slightly significantly related to subjective well-being and social self-efficacy and school engagement, which were included as mediator variables. Correlation findings showed that subjective well-being was also positively and moderately significantly related to social self-efficacy and school engagement. It was also seen that there was a positive and moderately significant relationship between the mediator variables of the study (social self-efficacy and school engagement). Finally, in the analysis of the study, the indirect effect of social media addiction’s level on subjective well-being was evaluated through both social self-efficacy and school engagement, and the relationship was found to be significant.</p>