PURPOSE: To provide an automotive hand-free talking unit in use of a portable radiotelephone.

CONSTITUTION: A holder 2 is installed in front of a driver's seat at an inner panel and connected to an outer amplifier 5 and an outer microphone 7 of a hand-free unit 3. A portable radiotelephone 1 is supported by the holder 2, and when a jack 17 at the tip of an extended cord 16 of the holder 2 is connected to an earphone-mike terminal 18, it is made hand-freely talkable. A receiving aural signal of the portable radiotelephone 1 is amplified by the outer amplifier 5, being converted into a receiving voice and amplifyingly outputted out of an outer speaker 6, while a transmitting voice inputted out of the outer microphone 7 is radio-transmitted to a counterpart side from the portable radiotelephone 1.