An apparatus for detecting biometric information, the apparatus comprising: at least one light source configured to radiate light to a surface of an object; a surface pulse wave measurement unit comprising: a plurality of first photodetectors configured to measure an intensity of light radiated by the at least one light source and reflected from the surface of the object; and and wherein the surface pulse wave measurement unit is configured to measure a surface pulse wave of the object based on the measured intensity of the light; a photo-plethysmogram measurement unit comprising a plurality of second photodetectors configured to measure a photoplethysmogram signal of the object; and wherein a biometric signal extractor configured to extract a plurality of biometric signal parameters based on the measured surface pulse wave of the object and the measured PPG signal; wherein the plurality of second photodetectors of the PPG measurement unit are disposed around the at least one light source; and the plurality of first photodetectors of the surface pulse wave measurement unit and the plurality of second photodetectors of the PPG measurement unit are alternately disposed around the at least one source in a direction along the circumference of the light source; wherein the apparatus further comprises a guide portion fixing the at least one light source, the plurality of first photodetectors and the plurality of second photodetectors, such that the first photodetectors are separated from the surface of the object when the second photodetectors contact the surface of the object, the guide portion further including a plurality of partitions (13a, 13b, 13c, 13d, 13e, 13f) between neighbouring photodetectors of the first plurality of photodetectors and second plurality of photodetectors. at least one light source configured to radiate light to a surface of an object; a surface pulse wave measurement unit comprising: a plurality of first photodetectors configured to measure an intensity of light radiated by the at least one light source and reflected from the surface of the object; and and wherein the surface pulse wave measurement unit is configured to measure a surface pulse wave of the object based on the measured intensity of the light; a plurality of first photodetectors configured to measure an intensity of light radiated by the at least one light source and reflected from the surface of the object; and and wherein the surface pulse wave measurement unit is configured to measure a surface pulse wave of the object based on the measured intensity of the light; a photo-plethysmogram measurement unit comprising a plurality of second photodetectors configured to measure a photoplethysmogram signal of the object; and wherein a biometric signal extractor configured to extract a plurality of biometric signal parameters based on the measured surface pulse wave of the object and the measured PPG signal; wherein the plurality of second photodetectors of the PPG measurement unit are disposed around the at least one light source; and the plurality of first photodetectors of the surface pulse wave measurement unit and the plurality of second photodetectors of the PPG measurement unit are alternately disposed around the at least one source in a direction along the circumference of the light source; wherein the apparatus further comprises a guide portion fixing the at least one light source, the plurality of first photodetectors and the plurality of second photodetectors, such that the first photodetectors are separated from the surface of the object when the second photodetectors contact the surface of the object, the guide portion further including a plurality of partitions (13a, 13b, 13c, 13d, 13e, 13f) between neighbouring photodetectors of the first plurality of photodetectors and second plurality of photodetectors.