Abstract: In view of the complex terrain environment,wide range of expertise,difficulty in planning and site selection,and problems of inaccurate terrain data acquisition,low coordination efficiency,and schedule management in the water conservancy project,a full life cycle construction application framework based on BIM+GIS technology is proposed. BIM technology is used to establish a refined model,GIS provides real three-dimensional terrain scene information,analyzes the two data fusion problems,and studies the method of integrating BIM models,oblique photographic data and other multi-source data into the three-dimensional GIS platform for integration. The multi-level and multi-dimensional information fusion combining micro and macro,virtual and reality is realized,and a three-dimensional visualized interactive environment is built. Taking a pumped storage power station as an example,it is applied in the planning,design,construction,operation and maintenance stages of a water conservancy project to achieve accurate and coordinated expression of project information such as progress,cost,quality,and safety,which is the full life cycle of a large water conservancy project management application provides a new way of thinking and improves the level of digital construction of water conservancy projects.