PROBLEM TO BE SOLVED: To provide a biological information detection device capable of detecting a driver's pulse wave velocity with high accuracy. SOLUTION: A control unit 40 radiates a first main transmission radio wave f11a to a portion where a pulse wave of a driver D can be detected, and a first main transmission radio wave f11a to a portion where a core trajectory of the driver D can be detected. 2 The main transmission radio wave f21a is radiated, and further, the transmission radio waves f12a and f22a are radiated according to the driver's seat DS. Further, the control unit 40 causes the receiving unit 30 to receive the first and second main reflected radio waves f11b and f21b and the secondary reflected radio waves f12b and f22b. Then, the control unit 40 calculates the difference between the first main reflected radio wave f11b and the secondary reflected radio wave f12b to derive a pulse wave waveform corresponding to the pulse wave, and at the same time, the second main reflected radio wave f21b and the secondary reflected radio wave f22b The difference between the two is calculated to derive the cardiac trajectory waveform according to the cardiac trajectory, and the pulse wave propagation time is detected from the difference between the peak in the pulse wave waveform and the peak in the cardiac trajectory waveform. [Selection diagram] Fig. 1【課題】運転手の脈波伝搬速度を高精度に検出できる生体情報検出装置を提供する。【解決手段】制御部４０は、送信部２０に、運転手Ｄの脈波を検出可能な部分に第１主送信電波ｆ１１ａを放射させると共に、運転手Ｄの心弾道を検出可能な部分に第２主送信電波ｆ２１ａを放射させ、さらに、運転席ＤＳに従送信電波ｆ１２ａ、ｆ２２ａを放射させる。また、制御部４０は、受信部３０に、第１、第２主反射電波ｆ１１ｂ、ｆ２１ｂおよび従反射電波ｆ１２ｂ、ｆ２２ｂを受信させる。そして、制御部４０は、第１主反射電波ｆ１１ｂと従反射電波ｆ１２ｂとの差を演算して脈波に応じた脈波波形を導出すると共に、第２主反射電波ｆ２１ｂと従反射電波ｆ２２ｂとの差を演算して心弾道に応じた心弾道波形を導出し、脈波波形におけるピークと、心弾道波形におけるピークとの差から脈波伝搬時間を検出する。【選択図】図１
