School administrators' face significant challenge in addressing bullying in schools. This study utilized multiple case studies to investigate the forms, challenges, resolving mechanism, and intervention plan on anti-bullying of three (3) school administrators of different laboratory schools in Leyte Philippines, purposely selected as respondents. It employed Colaizzi's descriptive phenomenological method of data analysis anchored on social cognitive theory utilizing in-depth semi-structured interviews, questionnaires, and voice recordings to gather data. Through triangulation, findings revealed that common forms of bullying were verbal and non-verbal: student to student, student to pre-service teacher, parent to pre-service teacher. The administrators ' challenges were handling bullies, bullied children, pre-service teachers, and parents. Conducting regular parents-teachers meetings, effective classroom management, clear policy on anti-bullying, orientation both to students, parents, pre-service teachers were the measures initiated by the school. Results of the study point out to school administrators to review policies and provide vital counseling programs on anti-bullying. Future directions also emphasize the development and implementation of anti-bullying education to promote positive interaction among students, pre-service teachers and parents.