Introduction: Accelerating forest ecosystem degradation and limited public environmental financing have increased the need for innovative and sustainable conservation funding mechanisms. This study aims to analyze the hybrid green waqf financing model implemented by Yayasan Pendidikan Sosial dan Ma'arif (YPM) Sidoarjo, Indonesia, to support forest ecosystem sustainability. Methods: This study employed a qualitative case study approach using semi-structured interviews, field observations, and document analysis. Informants were purposively selected from institutional leadership, operational management, and administrative personnel, while the data were analyzed using an interactive thematic analysis. Results: The findings indicate that YPM has developed a hybrid green waqf financing model integrating institutional waqf assets, grant-based technological support, digital fundraising, community-based philanthropy, stakeholder engagement, and trust-based governance. Institutional waqf land functions as a long-term ecological endowment, whereas grants and digital fundraising strengthen conservation capacity, public participation, and financial sustainability. However, limited cross-sector collaboration and low public literacy regarding green waqf remain significant implementation challenges. Conclusion and suggestion: Hybrid green waqf financing provides a viable Islamic social finance mechanism for sustainable forest conservation. Strengthening stakeholder collaboration, improving green waqf literacy, and developing supportive regulatory frameworks are recommended to enhance the scalability and long-term sustainability of conservation financing.