The study aimed to describe the level of mentoring self-efficacy and unfold the experiences and insights of the selected cooperating teachers in the Kapalong West District, Kapalong East District and Magatos Integrated School. This study employed a mixed-methods design, utilizing a parallel convergent approach. The participants of the study were cooperating teachers from the selected Kapalong West District Schools, Kapalong East District and Magatos Integrated School, which involved 96 teachers through stratified random sampling utilizing proportional allocation for the quantitative phase and 14 for the qualitative phase: seven for in-depth interviews and seven for focus group discussions, all of whom were purposively selected. Based on the results of the study, it was determined that the level of mentoring self-efficacy is high. The extracted themes on the experiences and insights include building confidence through experience, navigating challenges in mentoring roles, fostering professional growth in interns, balancing multiple responsibilities, and cultivating positive mentor-mentee relationships. The results from both the quantitative and qualitative data converged during corroboration, confirming that despite challenges and limited training on mentorship, cooperating teachers exhibit a strong sense of mentoring self-efficacy, which plays a crucial role in shaping effective teacher preparation and enhancing the professional development of pre-service teachers.