If the facsimile machine on the called side detects a facsimile signal such as a CNG signal sent from the calling side after the initiation of the recording operation, the facsimile machine on the called side is switched to the facsimile operation. If the timing for switching to the facsimile operation is within a prescribed period from the initiation of the recording, the facsimile machine on the called side considers that a facsimile message is sent from the calling side without voice message. Then, the data recorded on the called side is erased. If the timing for switching to the facsimile operation is after the prescribed period from the initiation of the recording, the facsimile machine on the called side considers that a facsimile message is sent from the calling side after a voice message. In this case, the data recorded on the called side is maintained.