A device for measuring biological information includes at least one light emitting element configured to emit light having predetermined wavelength, a light receiving element configured to receive returned light from a subject with respect to the emitted light, an attachment determination unit configured to determine whether the device is attached to the subject with respect to the light receiving element based on an amount of returned light received, and a measurement-point determination unit configured to determine whether or not a point where the device is attached to the subject is suitable for measuring the biological information based on the amount of returned light received, when the attachment determination unit determines that the device is attached to the subject.