PURPOSE: To automatically erase voice information from a storage means at a prescribed time, by providing the storage means for storing a voice data, and a means for erasing the voice data of this storage means at a prescribed time.

CONSTITUTION: A voice input which follows a voice accumulation request signal is accumulated in a memory through a voice use IC, and by the voice accumulation request signal, a CPU 1 starts a timer and manages the time. In this case, to two or more voice information, different memory areas are allocated, and the CPU 1 manages the time with regard to each of them. In this state, with respect to some information which has been accumulated, whether 24 hours have elapsed or not is judged with regard to each of them, and this judgement is executed at any time at every prescribed time. As for that which has exceeded 24 hours, its contents are erased. Said series of steps can be used properly by a user's convenience, by setting them so as to be performed only when some mode has been selected by a switch, etc.