The deep sea fuels the world’s largest ecosystem, and a deep knowledge of its relevant evolutionary patterns can support the sustainable development of human society. It is difficult to carry out in-situ experiments under the extreme environmental conditions in the deep sea, which puts forward harsh requirements for the development of deep-sea scientific experiment equipment. This study summarizes the development status and problems regarding deep-sea scientific experiment equipment in China and abroad from the aspects of deep-sea test equipment and test sites, deep-sea in-situ exploration and experiment equipment, and experimental equipment for deep-sea environment simulation. China has independently developed a serial of equipment and technologies in the field of deep-sea scientific experiment equipment, and some of its advantageous directions have reached the international advanced level, which has promoted the progress of deep-sea scientific research. However, the country fails to build a mature industrial chain in terms of sophisticated equipment and associated key technologies, resulting in the restricted development of some equipment and prominent technological weaknesses. Therefore, we propose the following suggestions to promote deep-sea scientific research and the high-quality development of the deep-sea scientific experiment equipment: (1) strengthening top-level planning to coordinate technical research; (2) establishing incentive mechanisms to encourage innovation transformation; (3) building demonstration platforms and forming a standards system; (4) developing sensing technologies and accelerating the localization process; and (5) strengthening international cooperation to enhance innovation capacities.