PROBLEM TO BE SOLVED : To provide a system for converting real estate into securities, with which the satisfactory circulation of economy can be created by operating property by fluidizing real estate by promoting the conversion of real estate into securities.SOLUTION : In the system for converting real estate into securities, which is composed of a real estate owner 3, an investment vehicle 1 and an investor 2, a guarantee association 4 is established for collecting members concerned in the conversion of real estate into securities on the home page on the Internet, distributing various kinds of information to the members with the conversion of real estate into securities and guaranteeing the risk of the investor 2 accompanying the conversion of real estate into securities with the investment of the real estate owner 3 among the members and real estate securities are sold with guarantees.