Research on realistic content is actively underway. The development of realistic content centered on AR has gone beyond adding 3D virtual content to the real world using smartphones and has developed into Media Facade content that uses projection mapping on large buildings. Recently, as the demand for advertising content using Media Facade using Projection Mapping increases, education and system development for Projection Mapping content are required. For trainees learning Projection Mapping for the first time, creating objects and buildings to project poses a great challenge. Building objects and buildings requires a lot of resources and resources, and once created, it is not easy to use resources to change them again. In this paper, we propose Projection Mapping Simulation based on Unity 3D Engine for projection mapping education. Because the proposed Projection Mapping Simulation is based on the Unity 3D Engine, it can be used by trainees for free, and objects and buildings can be represented and manipulated using various 3D Object Files. In addition, the video used for projection mapping can be used not only as video but also for real-time 3D rendering. We hope that the Projection Mapping Simulation proposed in this paper will be a place for experimentation to enhance trainees' understanding of space, objects, and buildings, and for Projection Mapping content researchers to experiment and research various projection mapping techniques.