Pulse rate calculating unit on the basis of the blood flow waveform representing temporal changes of blood flow of a living body, and calculates a pulse rate of a living body (110), based on the blood flow waveform, hypotension prediction device, the blood of the living and a hypotensive prediction unit based on a variation of each of the blood flow rate and the calculated pulse rate of blood flow calculator for calculating the flow rate (120), the calculated and predicted blood pressure lowering and (140).血圧低下予測装置は、生体の血流量の経時的な変化を示す血流波形に基づいて、生体の脈拍数を算出する脈拍数算出部(110)と、血流波形に基づいて、生体の血流量を算出する血流量算出部(120)と、算出された脈拍数及び算出された血流量の各々の変動に基づいて、血圧低下を予測する血圧低下予測部(140)とを備える。
