PROBLEM TO BE SOLVED : To provide a real estate index derivation system for deriving an index capable of contributing to objective determination of a worth of a real estate.SOLUTION : A real estate index derivation system comprises : a dealing number acquisition part TR for acquiring a number of land dealing which occurs in a predetermined period, in a predetermined zone; and an index derivation part IX for, based on the number of land dealing acquired by the dealing number acquisition part TR, and a number of a lot of the land existing in the zone where land dealing occurred, or an area of the zone where land dealing occurred, deriving an index related to mobility of the land.SELECTED DRAWING : Figure 1COPYRIGHT : (C)2016, JPO&INPIT