Eco-environmental damage incidents can destroy or damage the habitats of animals and plants and the balance of ecosystems, and even threaten China's ecological security. However, there are some problems in the current forest ecosystem damage assessment work, such as imperfect eco-environmental damage assessment system on forest ecosystem, inadequate quantitative assessment methods, and imperfect management system of damage compensation. And most of the related researches have focused on the damage to forest natural resources and ecosystem services, but lack of analysis on the overall damage of the interaction between human activities and forest ecosystem. Based on this, an assessment index system of forest ecosystem damage was established, which followed the four principles of scientific, systematic, comparability, and operability. The damage category and boundary of human activities and status of forest ecosystems were comprehensively considered, and the possible overlapping contents of human activities damage and the provisioning service and cultural service damage of forest ecosystem function were eliminated in the index system. Based on the damaged objects, the assessment index system involved a total of 4 first-level indicators of the losses of personal safety, human activities, forest ecosystem functions and others, including 14 second-level indicators of physical damage, mental damage, economic forest fruit loss, forest by-product loss, processing and manufacturing industry loss, forest tourism loss, scientific research and history loss, soil conservation loss, water conservation loss, sand fixation loss, carbon fixation and oxygen release loss, air purification loss, emergency treatment fee, investigation and evaluation fee, and then further refined into 22 three-level indicators. Moreover, the market value method, substitution cost method, shadow engineering method and recovery cost method were used to quantify the value of each indicator. The management system of forest ecosystem damage was also discussed from two aspects of forestry technology department and judicial administration department, respectively. The management system of forestry technology department was mainly divided into pre-prevention, in-process response and post- evaluation, including safety planning, risk control, damage tracing, emergency rescue measures, the establishment of technology program and restoration standard, etc. The management system of judicial administration department was mainly divided into supervision management, legislative management and social mechanisms, including register record (compilation), illegal accountability, improvement of compensation system, establishment of forest damage funds public participation methods, etc. This study aims to provide a reference for the quantification and standardization of assessment system and the improvement of management system and legislation mechanism of forest ecosystem damage.