To provide a biological information measurement device that facilitates change of dimensions in manufacturing, and can reduce a burden imposed on subjects by long-time wearing on a finger, the biological information measurement device includes a body part and a wearable part that is integrally attached to the body part and is to be worn on a finger of a living body, and includes a light source unit and a light receiving unit that are arranged so as to oppose each other with the finger therebetween when the wearable part is worn on the finger. The body part includes an electric circuit that includes a signal processing unit, a power supply unit, and a first terminal unit that is electrically connected to the electric circuit, and the wearable part includes at least one of the light source unit and the light receiving unit, and a second terminal unit that is electrically connected to the at least one of the light source unit and the light receiving unit. The first terminal unit and the second terminal unit are mechanically in contact with and electrically connected to each other. The signal processing unit acquires a digital value concerning a pulse wave based on a signal output from the light receiving unit by the light receiving unit receiving light that is emitted from the light source unit and passes through the finger.