PURPOSE : A real estate investment index calculation method is provided to compare investment value with regard to a plurality of real estates to supply a reliable investment index to an investor who will select a real estate for investment.CONSTITUTION : A user terminal is connected to a real estate investment index calculation server(S10). Plural real estates that an investor wants to compare in the user terminal are selected(S20). Data necessary for calculating a real estate investment index about each selected real estate is input to the real estate investment index calculation server through the user terminal(S30). Break-even point is calculated in the real estate investment index calculation server based on input data per each selected real estate. An investment index is calculated based on the break-even point(S40).? KIPO 2009