Unmanned underwater vehicles (UUVs) are important technical equipment for human beings to explore and exploit the ocean, and the R&D capability of UUVs marks the technical level of national deep-sea resource investigation and marine scientific research. This paper briefly introduces the development status of deep-sea UUVs abroad and focuses on the research progress of China’s deep-sea UUVs with the depth ratings of 4500 m, 6000 m, and 11000 m (full ocean depth). Moreover, this paper expounds on the important role of China’s deep-sea UUVs in deep-sea mineral resource investigation and deep-sea scientific research, as well as the constructed technical equipment system for exploration and operation at full ocean depth. Upon the analysis of the challenges faced by China’s deep-sea UUVs, some suggestions for future development are put forward.