IIn Turkey, real estate that is subject to ownership rights secured constitutionally can be expropriated upon cash payment of its value, in accordance with the Expropriation Law. Buildings are indispensable and immovables for life in meeting economic and social needs, especially housing. The continuation of these functions of the buildings will be ensured by determining their real values in case of expropriation. For this purpose, it is of great importance for the appraisers to know the technical principles of valuation, to be knowledgeable about the real estate market, and to consider the economic and social aspects of expropriation. The purpose of this article is to reveal the theoretical principles of value determination in buildings within the framework of the Expropriation Law