PROBLEM TO BE SOLVED: To provide a biological information measurement device excellent in portability and allowing biological information to be measured while a subject lives a daily life.SOLUTION: An analog electric signal S1 is generated by receiving scattered light L2 by a photodetector 103 when light L1 is emitted to a subject 102 from a light source 101, an amplified electrical signal S3 amplifying the signal with amplifying means 104 and 105 is generated, and it is converted into a digital signal data string D2 by ADC means 107. When a frequency spectrum of the digital signal data string D2 is analyzed by computation means 108 to measure biological information data, the digital signal data string D2 is generated by the ADC means 107 in the state in which power to be supplied to the light source 101 and the amplifying means 104 and 105 by control means 10 is increased, power to be supplied to the light source 101 and the amplifying means 104 and 105 is decreased, and by intermittently repeating processing until biological information data is generated by the computation means 108, the biological information data is intermittently measured.
