To analyze the vibration transmission characteristic, in response to the operating state of an actual engine.

This vibration transmission characteristics analyzer for an engine block comprises an exciting device 130, that is connected to a knock sensor mounting hub 163 disposed in a cylinder block 161 and excites the engine block 160 only for a period (t), defined as the duration of vibration when knocking actually occurs; a cylinder block vibration detecting sensor, arranged on the inner surface of a cylinder bore of the cylinder block 161; and a cylinder head vibration detecting sensor, arranged in a plug hole disposed in a cylinder head 162.