Abstract: A bi-point detection type heart-rate monitor is constructed to include two electrically conductive contact terminals for the touching of the two hands or feet of a person, an amplifier-filter circuit adapted to sample impedance signal between the contact terminals, to amplify the impulse of the sampled impedance signal, and to remove noises from the sampled impedance signal, a waveform converter adapted to rectify outputted waveform from the amplifier-filter circuit into a square wave, and a processing and output circuit adapted to receive and process the square wave signal outputted by the wave form converter, to obtain the mean frequency of peaks of the received square wave signal by means of a computing process, and to output the frequency value thus obtained to a display unit for display.