Abstract: Forest plays an important role in ecological environment protection. Among them, the forest water conservation function has been widespread social attention. After more than half a century of development, the cognition of forest water conservation function has made certain progress, mainly including forest water conservation function mechanism, value evaluation, construction and management, etc.. However, in some key level has not yet formed a unified cognition, such as the connotation of conservation function boundary, process mechanism, etc., which ignores the integrity of the hydrological process and the comprehensive impact on meteorological and soil factors, so make the field of research practice application is seriously limited, make the results of the regional targeted insufficient. Therefore, the article based on the forest ecosystem water conservation function research situation, depth, the concept of forest water conservation function connotation, formation process and comprehensive characteristics, and the different regional water conservation function connotation and leading service is clearly defined, and based on the research progress suggestion and prospects, in order to provide reference services for the function assessment and forest management. It provides a scientific basis for the comprehensive improvement of the forest water conservation function and the ecological restoration project of the water conservation forest in different regions.