The building is one of the most major energy-consuming sectors and for this reason we should pay a special attention to the optimizing the energy consumption in the building. From general point of view, it can be said that we can take an effective step in order to improve the energy optimization in the buildings by informing people, redacting proper legislations and reforming prices by gradual eliminating the state subsidies but generally replacing of renewable energies instead of fossil fuels that they are most major energy source, is a solution that its characteristic is foresight and respecting for rights of both current and future generations. Therefore, knowing the available technologies to use solar energy, and using of the results of conducted researches in other countries, that a short overview has been done on the most recent of them in the current article, will give many helps to advance this important issue. In this paper, in addition of overviewing of solar energy, it is paid to basic principles of solar technology and a variety of its applications for production of various energies in the building and using terms of this types of energy and optimizing the energy consumption in the process of buildings air conditioning. This research has been in types of descriptive and library and the results show that using of solar energy and its application in the field of the buildings air conditioning is an inevitable matter.