To estimate simply and accurately a vibration characteristic of an object architecture.

This vibration characteristic estimation method, which is a vibration characteristic estimation method for estimating a vibration characteristic of a structure to be estimated including a unit structure expressed by a plurality of physical quantities, includes the first measuring step wherein the structure to be estimated to which an additional structure expressed by a plurality of physical quantities including a reference physical quantity set at the first value is attached is vibrated into the first vibration state, and an element showing the first vibration state is measured; the second measuring step wherein the structure to be estimated to which the additional structure having the reference physical quantity set at the second value is attached is vibrated into the second vibration state, and an element showing the second vibration state is measured; and a determination step for determining the plurality of physical quantities for expressing the unit structure by solving an equation of motion wherein a motion of the structure to be estimated to which the additional structure is attached is expressed by a plurality of physical quantities, by using the first equation generated by the element showing the first vibration state and the second equation generated by the element showing the second vibration state.