Hydrogen is the ultimate clean energy to achieve zero carbon emissions. The storage and transportation of the liquefied hydrogen at sea has the characteristics of high storage and transportation efficiency and low long-distance transportation costs, which are crucial for the promotion and use of hydrogen energy worldwide. In the transnational and transregional liquefied hydrogen trade, large-capacity liquefied hydrogen carriers are the most economical, convenient and flexible storage and transportation tools, as well as strategic marine equipment with high technical difficulty and promising market value in the future. At present, the design and construction projects of the liquefied hydrogen carrier in the world are gradually increasing. Japan, South Korea and some European countries have taken the lead in exploring the cross-border liquefied hydrogen trade, and have conducted the corresponding research on the marine liquefied hydrogen carrier. However, research on the liquefied hydrogen carrier in China is still in the conceptual design stage, and the formulation of relevant specifications and guidelines is also in the early stage. The technical development and characteristics of the overall design, the liquefied hydrogen containment system, the liquefied hydrogen cargo handling system and the power system of the liquefied hydrogen carrier are analyzed to provide technology reference and guidance for the research, development and design of the liquefied hydrogen carrier and relevant equipment.