An information management system includes: an audio signal acquisitor configured to acquire an audio signal representing a guide voice; a related information acquisitor configured to acquire related information that is related to the guide voice; an association manager configured to associate the related information acquired by the related information acquisitor for the guide voice with identification information that is notified to a terminal device upon emission of the guide voice corresponding to the audio signal; and an information provider configured to receive from the terminal device an information request including the identification information notified to the terminal device and to transmit to the terminal device the related information associated by the association manager with the identification information.