The invention provides a photoelectric detector array, which comprises a sub-wavelength grating with a beam splitting function and a photoelectric detector set positioned above the sub-wavelength grating. A bonding medium layer is arranged between the sub-wavelength grating and the photoelectric detector set. When an incident light signal with high power, a high speed and a high dynamic range is processed, the high-performance sub-wavelength beam-splitting grating which is comprised by the photoelectric detector array splits the light signal into multiple beams of light signals with low power and small dynamic ranges, each distributed photoelectric detector in the photoelectric detector array respectively carries out photoelectric conversion, and an electrical signal generated by each photoelectric detector is superposed at a position of a large electrode so as to reduce an original injection signal. According to the scheme, the photoelectric detector array overcomes the defect that a single photoelectric detector cannot process a light signal with excessively high power and an excessively large dynamic range, and also overcomes the defects of complex coupling mode and preparation process of a conventional photoelectric detector array; and compared with the single photoelectric detector and the conventional photoelectric detector array, the photoelectric detector array provided by the invention has the characteristics of simple process, easiness for preparation, high saturation power, large dynamic range and high responsivity.