Developing a sustainable educational quality culture has become a strategic priority in improving school performance and preparing educational institutions to meet global standards. However, most teacher professional development programs remain focused on individual capacity enhancement rather than establishing a sustainable quality culture through integrated institutional approaches. This community service program aimed to transform educational quality culture through international collaboration between SDN Argasari 2 Kabupaten Ciamis, Indonesia, and Ban Donrak School, Thailand. The program adopted a participatory and collaborative approach consisting of four integrated strategies: capacity building, coaching and mentoring, cross-cultural collaboration, and technology-supported professional learning. Activities included workshops, professional mentoring, sharing of best educational practices, and the utilization of digital learning platforms to facilitate continuous collaboration. The implementation demonstrated improvements in teachers' and school leaders' understanding of quality culture, strengthened professional collaboration, enhanced instructional leadership, and expanded international professional networks. In addition, integrating digital technology supported continuous communication and professional learning beyond the formal program implementation. The program also produced a conceptual model illustrating the synergy among the four strategies in fostering a sustainable educational quality culture. These findings indicate that integrating professional capacity development, continuous mentoring, international collaboration, and digital technology provides an effective approach for strengthening educational quality culture in primary schools and offers a replicable model for similar educational contexts.