In an apparatus adapted to measure a pulse rate of a subject, a plurality of band pass filters, each of which has a center frequency that is different from the others are provided. The band pass filters are connected in parallel to one another so as to be adapted to receive a first signal corresponding to a pulse wave of the subject and be operable to output a plurality of second signals each of which is obtained by filtering the first signal with each center frequency. A first processor is operable to obtain a fundamental frequency of the first signal. A selector is operable to select one of the second signals which is output from one of the band pass filters having such a center frequency that is closest to the fundamental frequency. A second processor is operable to calculate the pulse rate from the selected one of the second signals.