This study aimed to determine School Heads’ Management Style and Academic Optimism as predictors of Teacher professionalism in six schools of Kidapawan City District I, Kidapawan City Division. A convergent approach was used and it is a type of design in which qualitative and quantitative data are collected in parallel, analyzed separately, and then merged. A total of 205 teachers were selected using the purposive sampling technique. Sets of adopted survey tools and interview guide were used to gather data from the participants. The mean, standard deviation, and multiple regression analysis were used as statistical tools. On the other hand, thematic analysis was used for qualitative data analysis. The findings revealed that the level of schools head’s management style and academic optimism are high among schools. Moreover, school head’s management style and academic optimism significantly influence teachers’ professionalism. The lived experiences of participants pertaining to teachers’ professionalism include themes such as contextualizing teachers’ professionalism at school, implementing various teaching strategies and better communication skills and importance of institutional support to improve teachers’ professionalism. In addition both quantitative and qualitative findings manifest converging results. In the aspect of teachers’ professionalism, the quantitative results on shaping and sharing vision reveals the commitment to change practices and innovate traditional styles in teaching to meet organizational objectives of teachers which are parallel to qualitative findings of the core ideas named teaching strategies that teachers should have abilities, strategies and styles in teaching the learners that emerged from thematic analysis. On taking initiatives, the data express parallelism in terms of findings particularly in initiative to improve professionalism that talks about the improvement of knowledge, skills and practices to transform pupils and be an effective educator. Furthermore, on building teacher-learner support, the results express parallelism in developing good relationship that tells about attitudes and values of teachers in dealing with pupils, colleagues and stakeholders. It is also converged in capability building support that entails about trainings and seminars that teachers need to develop their skills and management.