A biological information detector includes a light-emitting part, a reflecting part, and a light-receiving part. The light-emitting part is configured and arranged to emit light directed at a detection site of a test subject. The reflecting part is arranged at the periphery of the light-emitting part. The light-receiving part is configured and arranged to receive reflected light at the detection site including biological information. The light-emitting part and the light-receiving part are arranged not to overlap each other in plan view. A distance between the detection site and the light-emitting part is different from a distance between the detection site and the light-receiving part.
