A notification sound control unit of an approaching vehicle audible system includes a first rotation speed calculation section that calculates a first rotation speed, based on an accelerator opening degree signal of an electric vehicle, a second rotation speed calculation section that calculates a second rotation speed, based on a vehicle speed signal of the electric vehicle, a rotation speed synthesis section that synthesizes the first rotation speed and the second rotation speed, a virtual engine rotation speed calculation section that applies filtering processing to a synthesis rotation speed synthesized by the rotation speed synthesis section so as to calculate a virtual engine rotation speed, and a notification sound signal generation processing section that changes a pitch and a volume of a phoneme signal outputted from a phoneme, based on the virtual engine rotation speed, so as to generate a notification sound signal.