PURPOSE: To provide a volume controller capable of attaining a mute state meeting the demand of a listener.

CONSTITUTION: A control part 3 compares a normal sound volume value with a half-mute sound volume value and controls an audio amplifier part 1 so as to attain a half-mute state when a mute key is inputted while the normal sound volume value is larger than the half-mute sound volume value and so as to attain a complete mute state when the mute key is inputted while the normal sound volume value is equal to or less than the half-mute sound volume value. Thus, the optimum mute state corresponding to the normal sound volume value listened to by the listener can be attained.