This study aims to examine the process of internalizing religious values and its relation to students’ prosocial behavior in the context of an Islamic primary school, specifically at SD Rabbani Bandung. This study is motivated by the limited empirical understanding of how religious values are practiced and experienced in students’ daily activities at the elementary level. A qualitative case study design was employed. Data were collected through in-depth interviews, participatory observation, and documentation involving the principal, teachers, and students, and were analyzed using thematic analysis. The findings indicate that the internalization of religious values occurs through four main mechanisms: religious habituation, teacher modeling, positive reinforcement, and socio-religious experiences. Students who not only participate in activities but also understand and reflect on the values tend to demonstrate more consistent prosocial behaviors, such as helping, sharing, and cooperation. The results also highlight the importance of daily interactions and school culture in supporting the transformation of values into observable behavior. This study contributes by providing an empirical description of the process of value internalization in an Islamic primary school context and offering insights for developing more reflective, experience-based character education practices. Abstrak Penelitian ini bertujuan mengkaji proses internalisasi nilai religius dan kaitannya dengan perilaku prososial siswa di SD Rabbani Bandung. Penelitian ini menggunakan desain studi kasus kualitatif dengan pengumpulan data melalui wawancara mendalam, observasi partisipatif, dan dokumentasi yang melibatkan kepala sekolah, guru, dan siswa. Data dianalisis menggunakan analisis tematik. Hasil penelitian menunjukkan bahwa internalisasi nilai religius berlangsung melalui empat mekanisme utama, yaitu pembiasaan religius, keteladanan guru, penguatan positif, dan pengalaman sosial-keagamaan. Siswa yang memahami dan merefleksikan nilai-nilai tersebut cenderung menunjukkan perilaku prososial yang lebih konsisten, seperti menolong, berbagi, dan bekerja sama. Temuan juga menegaskan pentingnya budaya sekolah dan interaksi sehari-hari dalam membentuk perilaku siswa. Penelitian ini memberikan gambaran empiris tentang internalisasi nilai di sekolah dasar Islam serta menjadi masukan bagi pengembangan pendidikan karakter yang lebih refleif dan berbasis pengalaman.