A measurement device includes a plurality of detection units that respectively include a light emitting unit which emits light to a measurement target site and a light receiving unit which generates detection signals corresponding to a light receiving level of the light emitted from the light emitting unit and passing through the inside of the measurement target site, and a selection unit that selects some of the detection signals in accordance with an intensity index indicating signal intensity of the respective detection signals, from the detection signals generated by the light receiving unit in each of the plurality of detection units.
