The maintenance cost of buildings is came into question, it is accepted centering around a running cost and rarely the lite cycle cost combining a running cost with an initial cost. Accordingly, the development of the method to analyze and judge the life cycle cost and an effort of building must be needed, considering with a using term. In this report, I consider conditions, look for the system to calculate the life cycle cost, calculate and analize the life cycle cost in medium scale office building. I find that the use-management cost of building is very large, and that it influences the total cost how to decveace it.