PURPOSE: To decrease the number of times of reading out a voice message from a magnetic disk and to improve read-out efficiency of the voice message by writing the voice message whose read-out frequency is high in a RAM in advance.

CONSTITUTION: A control part 6 reads out the contents of a message counter 3, reads out a voice message whose read-out frequency is high in the voice messages stored in a magnetic disk part 1 at present, and writes it in a RAM 2. This operation is executed periodically, and in the RAM 2, the voice message whose read-out frequency is high at that time point is always written. When it is requested to reproduce the voice message from a user of a telephone set 7, the control part 6 reads it out from the RAM 2, when the requested voice message is written in the RAM 2, and reads it out of the disk part 1 only when it is not written. In such a way, the number of times of reading out the voice message from the magnetic disk is decreased, and the read-out efficiency of the voice message is improved.