In a pulse wave signal processor, a first filter attenuates a frequency component in an acquired pulse wave signal or in a differentiated pulse wave signal, and the attenuated frequency component is more than or equal to a first frequency. A second filter attenuates a frequency component in the acquired pulse wave signal, and the attenuated frequency component is less than the first frequency and more than or equal to a second frequency. A characteristic-point extractor extracts a characteristic point that exists in each single pulse of the pulse wave signal filtered by the second filter, and a signal separator partitioning the pulse wave signal or the differentiated signal filtered by the first filter into sections such that each section includes one of the extracted characteristic points. The partitioned sections are overlapped such that the characteristic points are coincident with each other, and arithmetically averaged.