A method for measuring vibration properties of a structure (140, 240, 340, 440) by applying an impulse input to the structure (140, 240, 340, 440), comprising: step of pulse-irradiating the surface of the structure (140, 240, 340, 440) or the vicinity of the surface with a laser beam (120, 220, 320, 420) to apply an impulse input to the structure (140, 240, 340, 440) and measuring a response output from the structure (140, 240, 340, 440) to which the impulse input has been applied, the impulse input generating vibrations of the structure; step of determining a relationship between the laser intensity of the laser beam and the magnitude of the impulse input induced by the laser beam by a rigid pendulum method, and determining the magnitude F of the impulse input corresponding to the laser intensity of the laser beam (120, 220, 320, 420), with which the structure (140, 240, 340, 440) has been pulse-irradiated in step, on the basis of the relationship; and step of dividing a complex Fourier spectrum of frequency and vibration amplitude obtained from the response output measured in step, by the magnitude F of the impulse input determined in step, thereby calculating a complex Fourier spectrum normalized by the magnitude of the impulse input, wherein the impulse input is an impulse excitation force that is applied to the structure (140, 240, 340, 440) by pulse-irradiating the laser beam (120, 220, 320, 420) to the surface of the structure (140, 240, 340, 440) and generating ablation, or an impulse excitation sound pressure that is applied to the structure (140, 240, 340, 440) by pulse-irradiating the laser beam (120, 220, 320, 420) to the vicinity of the structure (140, 240, 340, 440) and generating breakdown, the response output is an acceleration response or a velocity response of the structure (140, 240, 340, 440), when the impulse input is an impulse excitation force, in step, the relationship is determined on the basis of Newton's second law from a power spectrum corresponding to the magnitude of the acceleration of a rigid body block (160, 260) when the surface of the rigid body block (160, 260) is irradiated with the laser beam to generate ablation, and the mass of the rigid body block (160, 260), when the impulse excitation is a sound pressure, in step, the relationship is determined on the basis of Newton's second law from a power spectrum corresponding to the magnitude of the acceleration of a rigid body block (160, 260) when the vicinity of the rigid body block (160, 260) is irradiated with the laser beam to generate breakdown, and the mass of the rigid body block (160, 260). step of pulse-irradiating the surface of the structure (140, 240, 340, 440) or the vicinity of the surface with a laser beam (120, 220, 320, 420) to apply an impulse input to the structure (140, 240, 340, 440) and measuring a response output from the structure (140, 240, 340, 440) to which the impulse input has been applied, the impulse input generating vibrations of the structure; step of determining a relationship between the laser intensity of the laser beam and the magnitude of the impulse input induced by the laser beam by a rigid pendulum method, and determining the magnitude F of the impulse input corresponding to the laser intensity of the laser beam (120, 220, 320, 420), with which the structure (140, 240, 340, 440) has been pulse-irradiated in step, on the basis of the relationship; and step of dividing a complex Fourier spectrum of frequency and vibration amplitude obtained from the response output measured in step, by the magnitude F of the impulse input determined in step, thereby calculating a complex Fourier spectrum normalized by the magnitude of the impulse input, wherein the impulse input is an impulse excitation force that is applied to the structure (140, 240, 340, 440) by pulse-irradiating the laser beam (120, 220, 320, 420) to the surface of the structure (140, 240, 340, 440) and generating ablation, or an impulse excitation sound pressure that is applied to the structure (140, 240, 340, 440) by pulse-irradiating the laser beam (120, 220, 320, 420) to the vicinity of the structure (140, 240, 340, 440) and generating breakdown, the response output is an acceleration response or a velocity response of the structure (140, 240, 340, 440), when the impulse input is an impulse excitation force, in step, the relationship is determined on the basis of Newton's second law from a power spectrum corresponding to the magnitude of the acceleration of a rigid body block (160, 260) when the surface of the rigid body block (160, 260) is irradiated with the laser beam to generate ablation, and the mass of the rigid body block (160, 260), when the impulse excitation is a sound pressure, in step, the relationship is determined on the basis of Newton's second law from a power spectrum corresponding to the magnitude of the acceleration of a rigid body block (160, 260) when the vicinity of the rigid body block (160, 260) is irradiated with the laser beam to generate breakdown, and the mass of the rigid body block (160, 260).