Under the guidance of the carbon neutrality goal, energy production and consumption modes of China are shifting to be green and low-carbon, and the hydrogen energy supply system will be reshaped based on green hydrogen. Green hydrogen will become an important component of China's new energy supply and consumption system. Strengthening the construction of a green-hydrogen supply system is conducive to the transformation of China's energy production and consumption modes. This study explored the significant values for constructing the green-hydrogen supply system and analyzed the challenges faced by the construction, including (1) spatial mismatch between green hydrogen supply and demand, (2) temporal mismatch between green hydrogen production and consumption, and (3) mismatch between the green-hydrogen supply system and existing systems, mechanisms, and standards. To support the construction of the green-hydrogen supply system, key research directions include key basic issues of hydrogen storage and transportation, hydrogen storage and transportation technologies and equipment, and safety testing technologies of hydrogen storage and transportation equipment, thereby realizing the high-quality development of hydrogen storage and transportation. Moreover, the study proposed the integrated development of hydrogen energy and electrical power to construct the green-hydrogen supply system of China. Hydrogen storage and transportation is a key link that connects water-electrolytic hydrogen production and hydrogen consumption and is crucial for adjusting the spatial and temporal mismatch of green hydrogen supply and demand and for realizing flexible supply of green hydrogen. Therefore, we suggest that China should focus on top-level design and overall planning, improve infrastructures to address the spatial and temporal mismatches, conduct pilot demonstration to drive technological innovation, and improve the systems and mechanisms to optimize the development environment.