An information distribution system includes a sound wave transmitter, a mobile terminal, and an information distribution device. The sound wave transmitter transmits identification information to identify the sound wave transmitter. The mobile terminal receives the identification information and transmits the identification information to the information distribution device. The information distribution device is configured to transmit distribution information related to the identification information received from the mobile terminal to the mobile terminal. The information distribution device counts a number of the mobile terminal that transmits each identification information every predetermined period and identification information and transmits the distribution information to the mobile terminal that transmits the identification information in which the number of the mobile terminal reaches a predetermined number.