An under-screen biometric identification apparatus, applicable to an electronic device having a display screen, wherein the display screen has a light leakage area and the under-screen biometric identification apparatus is mounted under the light leakage area of the display screen, wherein the display screen comprises a light emitting layer, a third quarter-wave plate and a second linear polarizer, wherein the third quarter-wave plate is disposed above the light emitting layer, the second linear polarizer is disposed above the third quarter-wave plate, the under-screen biometric identification apparatus comprising: an optical function layer, structured to be arranged under the light leakage area of the display screen, the optical function layer comprising a first linear polarizer, a first quarter-wave plate and a second quarter-wave plate, wherein the second quarter-wave plate, the first linear polarizer, and the first quarter-wave plate are arranged in a stack manner, the first linear polarizer is disposed between the second quarter-wave plate and the first quarter-wave plate, the first quarter-wave plate is disposed at a side of the optical function layer adjacent to the optical biometric sensor; an optical biometric sensor comprising an optical sensing array structured to be arranged below the optical function layer, wherein a biometric collection area of the optical biometric sensor is within a display area of the display screen; wherein the optical sensing array is configured to receive reflected light from a finger above the display screen and transmitted through the second quarter-wave plate, the first linear polarizer and the first quarter-wave plate, and convert the received light into biometric detection signal for biometric identification; wherein the optical biometric sensor is included in an optical identification module configured to perform biometric identification; and the first linear polarizer and the first quarter-wave plate are configured to weaken light reflected from the optical identification module from being transmitted to the display screen. an optical function layer, structured to be arranged under the light leakage area of the display screen, the optical function layer comprising a first linear polarizer, a first quarter-wave plate and a second quarter-wave plate, wherein the second quarter-wave plate, the first linear polarizer, and the first quarter-wave plate are arranged in a stack manner, the first linear polarizer is disposed between the second quarter-wave plate and the first quarter-wave plate, the first quarter-wave plate is disposed at a side of the optical function layer adjacent to the optical biometric sensor; an optical biometric sensor comprising an optical sensing array structured to be arranged below the optical function layer, wherein a biometric collection area of the optical biometric sensor is within a display area of the display screen; wherein the optical sensing array is configured to receive reflected light from a finger above the display screen and transmitted through the second quarter-wave plate, the first linear polarizer and the first quarter-wave plate, and convert the received light into biometric detection signal for biometric identification; wherein the optical biometric sensor is included in an optical identification module configured to perform biometric identification; and the first linear polarizer and the first quarter-wave plate are configured to weaken light reflected from the optical identification module from being transmitted to the display screen.