A biological information detector includes a substrate, a light-emitting element, a light-receiving element, and a bonding pad. The light-emitting element has a thickness of 20 μm to 1000 μm. The light-receiving element has a thickness of 20 μm to 1000 μm. The bonding pad is disposed at a position that overlaps the light-emitting element and that is displaced relative to a center of the light-emitting element in a plan view as viewed in a perpendicular direction perpendicular to an emitting surface of the light-emitting element. A wavelength of light emitted by the light-emitting element is within a range of 470 nm to 600 nm.
