A biological-information detecting apparatus includes a first blood-flow measuring device provided at a seat surface of a seat, the first blood-flow measuring device measuring a condition of a blood flow of a popliteal artery of a measurement subject seated in the seat, a second blood-flow measuring device provided at a back of the seat, the second blood-flow measuring device measuring a condition of a blood flow of a thoracic aorta of the measurement subject, and a blood-pressure calculation device determining a pulse-wave propagation velocity and a degree of arteriosclerosis from blood flow data acquired by the first blood-flow measuring device and blood flow data acquired by the second blood-flow measuring device and calculating blood pressures of the popliteal artery and the thoracic aorta of the measurement subject based on the pulse-wave propagation velocity and the degree of arteriosclerosis.
