At least a portion of embodiments of the present specification relates to a service mediating a real estate transaction between a buyer and a seller. More specifically, the present invention relates to a system and method for mediating a real estate transaction, which may register real estate for sale through an application installed on a mobile device or an application in an Internet portal environment, and may provide a service associated with an actual real estate transaction including contract of the registered real estate for sale, payment of the balance, and registration of the real estate through one application. The system includes an actual real estate transaction service server configured to upload real estate for sale, process one or more among reference, visit reservation and contract requested by a client terminal, and provide a real-time transfer service.(AA) Real estate agency(BB) Financial instiution(CC) Perform an actual real estate transaction(DD) Provide an application(EE) Dealer/Buyer(2) Financial transaction support(100) Actual real estate transaction service server(1) Register real estate for sale(400) Client terminal(300) Finance server(200) Real estate registration terminalCOPYRIGHT KIPO 2015