A sound volume control apparatus includes a sound acquisition section provided in a moving body to be ridden by a human for acquiring a sound in a surrounding of the moving body, a storage section for storing a sound acquired by the sound acquisition section as sound data, a calculation section for calculating time change in volume of the sound acquired in a period from a predetermined first past timing to the present, with using the sound data, a sound volume setting section for setting a volume of an alarming sound based on result of the calculation in the calculation section, and an alarming section for effecting alarming in the volume set by the sound volume setting section.
