[Objective] The carbon and water cycles in terrestrial ecosystems are the core of the material and energy cycles in terrestrial ecosystems, and also the link connecting the geosphere, the biosphere and the atmosphere. Forest vegetation is an important component of terrestrial ecosystems, an important variable characterized the terrestrial carbon-water cycle, and plays an important role in maintaining the dynamic balance of the biosphere and the atmosphere. Currently, there is a lack of systematic analysis and summary of the coupling relationship and mechanism of carbon-water cycle in terrestrial ecosystems. [Methods] This paper summarizes the research and its progress on forest vegetation carbon and water cycle processes and their interactions, as well as the definition, methods, progress and outlook of carbon-water coupling at different spatial scales (leaf to regional/global scales) from the perspectives of forest vegetation carbon and water processes and their interactions, and vegetation water use and coupling mechanisms, respectively. [Results] Emerging technologies and methods have realized high-frequency observations of hydrocarbon processes at different scales, and coupled indicator systems such as WUE have promoted the research and development of hydrocarbon coupling mechanisms.[Conclusion] In conclusion, we have systematically elucidated the multi-scale integration of vegetation carbon-water coupling relationship and carbon-water coupling mechanism, which provides a theoretical basis for the systematic understanding of forest carbon-water coupling mechanism and water resource management, and is of great significance as a scientific support for the future decision-making of vegetation operation and management.