Abstract Forests in San Mariano, Isabela, Philippines are invaluable resources facing threats from destructive activities and natural disturbances, resulting to significant forest loss. To address this challenge, this study introduces biotope mapping as a tool for forest conservation and management in San Mariano, Isabela. The goal is to identify and map the different biotopes in San Mariano, Isabela which helps in enhancing sustainable forest management strategies, ensuring the long-term preservation of forest ecosystems. By conducting site visits, utilizing remote sensing techniques and geographic information systems (GIS) analysis, the distribution and classification of biotopes in San Mariano are determined. Through overlaying the soil type map, land cover map, and landform map, 22 biotopes were determined, and each were visually presented by showing a section-elevation diagram of each biotope. Furthermore, an assessment was also done for each biotope providing a comprehensive understanding of the different biotopes within the study area. This also serves as a reference for prioritizing conservation efforts, establishing protected areas, implementing habitat restoration initiatives, and mitigating threats to forest ecosystems. The findings and recommendations of this study contribute to the promotion of effective forest conservation and management, ensuring the long-term preservation of the forested landscapes.