A large number of studies have demonstrated the role that teacher self-efficacy plays in teaching and learning, as well as in the teacher's mental health. In this context, the article aims to analyse the relationship between teacher self-efficacy, job satisfaction, and the state of well-being in terms of flourishing. To this aim, 180 teachers working in the pre-university public education system (Mage=42,58; 127 females and 53males) recruited probabilistically, filled in three questionnaires. The first one is Teacher self-efficacy scale (TSES -Tschannen-Moran & Woolfolk Hoy), meant to assess the teachers' self-confidence regarding their ability to plan, to organize, and to carry out the activities needed to achieve educational purposes. The second one is Flourishing scale (FS -Diener et al.) and the third one is Teacher job satisfaction (TJS -Skaalvik & Skaalvik), meant to measure well-being and job satisfaction, respectively. Structural equation modeling based on the partial least square approach (PLS-SEM) was used in order to assess the relationship between variables. After ensuring the data have acceptable validity and reliability, the structural model was performed. The results show a significant correlation between job satisfaction, flourishing, and teachers' self-efficacy regarding the students' engagement, instructional strategies, and classroom management. The model highlights teachers' self-efficacy as a mediator between job satisfaction and well-being. Therefore, job satisfaction influences teacher self-efficacy, which, in its turn, contributes to teacher flourishing. The results are analyzed and compared to those in other pieces of research.