In our continuous exploration and exploitation of the ocean, marine robots are powerful tools for accessing oceanic environments that are sometimes harsh or even too dangerous for humans. Early marine robots acted under human supervision, executing preprogrammed tasks or working under the control of highly trained specialists. In recent years, with the advancements in hardware and software, marine robots have begun to possess the capability to autonomously sense and adapt to the intricate ocean environment, thus working more efficiently and intelligently. By integrating recent advances in science and technology, ranging from biomimetic technology and new materials to advanced artificial intelligence methods, marine robots have the potential to be more powerful in the exploration of the ocean environment and facilitating a broader spectrum of tasks, such as studying marine life in their natural habitats or performing inspections and dexterous manipulation in the deep sea.