With the increasing exploration, development, and utilization of China's oceans, rivers, and groundwater resources, as well as the increasingly urgent military need for sovereign defense in territorial waters, obtaining high-quality target images under long-distance underwater conditions has become an urgent problem to be solved in many fields, such as underwater environmental surveys, target detection, and enemy-self confrontation. Currently, the underwater imaging detection technology includes two main methods: acoustic and photoelectric detection. In this study, the current status of the main underwater high-resolution photoelectric detection imaging technology is studied, the advantages and disadvantages of different technical approaches are analyzed, and the photodetectors used in various underwater detection/imaging systems are compared. Combined with its own technical background, it is proposed that the development of a GaAsP photocathode dual microchannel plate image intensifier with high sensitivity, low noise, high gain, fast response, wide dynamic range, and good linearity should be accelerated to simplify the low sensitivity, high noise, low gain, and long processing time, owing to the poor performance of the detector in the photoelectric system, and accelerate the conversion speed of various new technologies into products and practical equipment. The results of this study support the development of underwater photoelectric imaging technology.