In a operating department for which the most integrated function is require, cleanliness must be kept and the safety of facilities, equipments and devices must be maintained any times. Furthermore, the working environment for medical staff such as doctors and nurses must be considered from the view point of human engineering. The modular operating theatre satisfying those conditions consists of wall, ceiling and slanted panels, and is capable of incorporating not only electronic equipment, medical gas system and lighting gears but all the necessary functions and equipments at need. In addition, the modular theatre has a high availability of extension providing for the introduction of new facility in the future, establishing as well an operating environment with high work ability and enough function. The most complex and challenging area of hospital construction and is the operating department. The Pre-fabricated Operating integrated