Abstract: A middle ear sound transmission characteristics evaluation system includes a probe; a measuring probe that includes an actuator that vibrates the probe and a force sensor that outputs a voltage in accordance with a reaction force exerted to the actuator when a tip of the probe is brought into contact with ossicles; an electrode that is installed on or near a round window and detects a potential value of a cochlear microphonic when vibration is applied to the ossicles by the probe; a database that stores a sensor voltage value output by the force sensor before surgical treatment, the potential value detected by the electrode, and surgical details; and a surgical details proposing unit that proposes selected surgical details on the basis of the magnitude of at least one of the sensor voltage value and the potential value measured before surgery with reference to the database.