The invention provides a data management apparatus which can use data advantageously in terms of data capacity. A database server performs a registration process and a providing process. When a data registration request is received from a seller, the registration process registers audio data included in the received data registration request in association with data name information, password information, and the like. At the same time, the registration process transmits usage certificate data that includes the information to a user. When a data usage request is received from a portable terminal, and when a password of a record in which the same data name as that included in the received data usage request is registered matches a password included in the received data usage request, the providing process transmits audio data specified by the data name included in the received data usage request to the portable terminal.