Abstract: Aiming at the demand for online training on reservoir dam patrol inspection, we studied serious games, put forward the architecture of reservoir dam patrol inspection training system on the internet, explored the key technologies of dam BIM modeling, inspection point and defect 3D modeling, reservoir hub scene simulation, analyzed the requirements, methods, equipment, contents for reservoir dam patrol inspection, and developed reservoir dam patrol inspection training system based on Unity3D. The reservoir dam patrol inspection training system is composed of the data layer, model layer and application layer, with the functions of patrol inspection knowledge, inspection training, inspection examination and system management. The reservoir dam patrol inspection training system has solved the problems of narrow coverage, high cost and long time in the traditional training methods. It can be widely used for the training of reservoir management personnel, especially those for small and medium-sized reservoirs without monitoring facilities or with damaged monitoring facilities, to further standardize the reservoir dam patrol inspection work, improve the patrol inspection capacity of reservoir management personnel, and ensure the safe operation of reservoir dams.