PURPOSE: To obtain a and-free telephone set enabling 2-way talking in which howling is prevented with simple processing.

CONSTITUTION: A transmission signal outputted from a transmission microphone section 11 is given to plural BPFs 130-139 having different pass frequency bands of BPF section 13, from which the signal of each frequency band is extracted and the signals are converted into DC level signals via rectifier circuits 140-149 of a rectifier circuit section 14. Then the signals are compared with signals at a predetermined level at each of comparators 150-159 of a comparator section 15. When there is a signal in excess of the predetermined level as the result of comparison, the signal corresponding to the frequency band in excess of the predetermined level is eliminated or attenuated by plural BEFs 160-169 having different elimination frequency bands in a BEF section 16 receiving the transmission signal from the transmission microphone section 11.