An apparatus for detecting biological information, the apparatus comprising: a biological signal measurement unit comprising a light emission portion and a photodetector, the light emission portion comprising at least two light emission elements (LL10, LL20) having at least two different light emission angles, wherein the at least two light emission elements (LL10, LL20) comprise a first light emission element comprising a first light source, and a second light emission element comprising a second light source, and a first light emission angle (θ1) of the first light emission element is greater than a second light emission angle (θ2) of the second light emission element, wherein the photodetector is configured to detect light (L50') generated by the light emission portion and modulated by a subject and to generate a plurality of signals based on the detected light (L50'), and a data processor configured to extract and analyze biological information of the subject based on the plurality of signals from the biological signal measurement unit; the apparatus characterized in that the data processor is configured to receive the first signals due to the first light emission element and the second signals due to the second light emission element, to select, from the first signals and the second signals, a signal having a high signal-to-noise ratio, SNR, higher than that of at least one of the first signals and the second signals, and to extract and analyze biological information of the subject using the selected signal; the biological signal measurement unit further comprises at least one spacer protruding toward one side of the biological signal measurement unit, wherein the at least one spacer separates the light emission portion and the photodetector from the surface of the subject; and the biological signal measurement unit is configured to measure a surface pulse wave of the subject. a biological signal measurement unit comprising a light emission portion and a photodetector, the light emission portion comprising at least two light emission elements (LL10, LL20) having at least two different light emission angles, wherein the at least two light emission elements (LL10, LL20) comprise a first light emission element comprising a first light source, and a second light emission element comprising a second light source, and a first light emission angle (θ1) of the first light emission element is greater than a second light emission angle (θ2) of the second light emission element, wherein the photodetector is configured to detect light (L50') generated by the light emission portion and modulated by a subject and to generate a plurality of signals based on the detected light (L50'), and a data processor configured to extract and analyze biological information of the subject based on the plurality of signals from the biological signal measurement unit; the apparatus characterized in that the data processor is configured to receive the first signals due to the first light emission element and the second signals due to the second light emission element, to select, from the first signals and the second signals, a signal having a high signal-to-noise ratio, SNR, higher than that of at least one of the first signals and the second signals, and to extract and analyze biological information of the subject using the selected signal; the biological signal measurement unit further comprises at least one spacer protruding toward one side of the biological signal measurement unit, wherein the at least one spacer separates the light emission portion and the photodetector from the surface of the subject; and the biological signal measurement unit is configured to measure a surface pulse wave of the subject.