The ocean contains abundant natural energy resources including several types of clean and renewable energy. Traditional ocean energy harvesting (OEH) systems based on large electromagnetic generators have shown limitations of inefficiency in harvesting irregular, low-frequency ocean energy. Triboelectric nanogenerators (TENG) have emerged as a promising new source of ocean energy, and it has shown significant technical advantages in applying low-frequency ocean energy-efficient harvesting. The self-driven energy system based on TENG has been successfully used in the ocean Internet of Things and distributed sensor systems, and breakthroughs have been made in integrating research and development with traditional electromagnetic power generation systems. In this paper, we systematically review the latest developments in ocean energy harvesting with TENG and analyze and summarize the principle, structure, efficiency, and performance of various types of TENG ocean energy harvesting systems, and the present challenges and future development trends of TENG in ocean energy collection and application are also pointed out.