BACKGROUND: Students in middle-income countries frequently experience stigma related to mental disorders (MDs). Those with MDs are stereotyped as incompetent, uncontrollable, uncooperative, and dangerous. Stereotypes are predominantly formed and disseminated due to culture and beliefs. Therefore, it is essential to investigate, comprehend, and apply the local values and beliefs to increase the effectiveness of school-based anti-stigma programs. AIM: This study aims to investigate the local values and beliefs related to mental health anti-stigma as early initiation of school-based anti-stigma development. METHODS: This is an exploratory phenomenological study. A total of 30 informants were interviewed personally or participated in focus group discussions. Content analysis was performed to identify related sub-themes and themes. RESULTS: This study identified seven themes and 15 sub-themes. The seventh theme included the importance of school-based anti-stigma, school-based anti-stigma approach, school-based anti-stigma method, media dissemination of school-based anti-stigma information, design of school-based anti-stigma information, the target group of school-based anti-stigma, and collaboration partners of school-based anti-stigma. CONCLUSION: Adolescents in middle school frequently experience stigma regarding their mental health from their peers. Using both Islamic and mental health approaches, integrating internal and external stakeholders, dispelling unfavorable misconceptions and stereotypes, encouraging students to understand and empathize with others, and reducing the harmful effects of mental health stigma were found to help reduce the stigma of mental illness.