This paper investigates ecological asset accounting methods tailored for agricultural cultural heritage sites, specifically through the ancient tea forest cultural landscape of Jingmai Mountain in Pu′er. These heritage sites globally act as reservoirs of extensive cultural history and ecological richness, yet they face increasing risks and challenges from urban expansion and modernization. (1) The research develops a comprehensive methodological framework that merges ecological, economic, and cultural valuation techniques. This framework identifies and evaluates crucial ecological assets such as land, water, vegetation, fauna, and microorganisms, categorizing their value into direct values (e.g., agriculture), indirect values (e.g., flood control), and non-use values (e.g., biodiversity and cultural heritage). (2) It emphasizes the necessity of integrating cultural heritage preservation with ecological stewardship. This dual approach supports the sustainability of both cultural and natural resources, underpinning broader conservation goals and necessitating innovative management strategies for heritage conservation. (3) The study advocates for sustainable management practices that maintain the ecological and cultural integrity of these vital sites. Through detailed ecosystem analysis, the paper proposes balanced policies that cater to both ecological preservation and the socio-economic needs of local communities, promoting a replicable model for similar heritage sites worldwide. Overall, this model exemplifies how to effectively utilize ecological and cultural assets for sustainable development, ensuring the coexistence of natural and cultural values in a harmonious environment.