A startup suggestion device that is mounted on a vehicle together with a driving support device for assisting a driving operation of a driver or taking a wheel, and suggests a startup of the driving support device to the driver, includes: a state value acquisition unit that acquires a state value indicative of a traveling state of the vehicle; a preference value acquisition unit that acquires a preference value reflecting the traveling state preferred by the driver; and a startup suggestion unit that suggests the startup of the driving support device according to a comparison between the state value and the preference value.