Abstract: Purpose As a clean secondary energy source with zero-emission combustion, hydrogen plays a significant role in China's energy transition. Liquefying hydrogen for storage and transportation is one of the most crucial methods to enhance its storage and transportation efficiency. However, hydrogen liquefaction is an energy-intensive process characterized by high specific energy consumption and low exergy efficiency. Method To reduce energy consumption and improve the liquefaction energy efficiency of the hydrogen liquefaction process, a process was designed based on a domestic LNG receiving terminal. This process utilizes LNG cold energy for precooling and a helium Brayton cycle for deep refrigeration, with a liquid hydrogen production capacity of 300 tons per day. The process utilizes natural gas from LNG vaporization as feedstock, producing hydrogen through steam methane reforming process. The by-product carbon dioxide is recovered through liquefaction to provide raw material for subsequent dry ice production. Based on the designed process, the process was modeled and optimized using HYSYS software and a particle swarm optimization algorithm. Analyses were conducted including energy analysis, heat exchange analysis, exergy analysis, and thermodynamic analysis. Results The results indicate that by recovering expansion work, the optimized process achieves a specific energy consumption, exergy efficiency, and coefficient of performance of 4.797 kWh/kg, 65.44%, and 0.276, respectively, demonstrating high liquefaction performance. Exergy analysis shows the total exergy loss of the process is 58589.63 kW. The ortho-para hydrogen converter and the heat exchangers contribute the most to this loss, accounting for 56.27% of the total. Among the equipment, heat exchangers and compressors exhibit the highest exergy efficiency, while expanders show lower exergy efficiency due to their low expansion temperatures. Composite curves analysis of the heat exchangers reveals that the cryogenic heat exchangers achieve high heat transfer efficiency owing to rational cold energy distribution. Conclusion This process realizes both hydrogen production and efficient liquefaction while satisfying the pressure requirements for LNG gasification and pipeline export. This study provides valuable insights for future utilization of LNG cold energy and the design of efficient hydrogen liquefaction processes.