Abstract: As a green energy, hydrogen energy plays a significant role and has a broad development prospect in the fields of new energy. Among various hydrogen production technologies, the water splitting is the most mature and promising green and commercial hydrogen production method. Designing and developing novel and efficient non-precious-metal-based electrocatalysts are of great importance for the large-scale applications of the water splitting for the hydrogen production. High-entropy materials refer to high-entropy alloys composed of five or more metallic elements and high-entropy compounds containing non-metallic elements. High-entropy materials exhibit unique properties like high-entropy effect, slow-diffusion effect, lattice-distortion effect and cocktail effect. Metal-organic frameworks (MOFs) are well known for their high porosity, large specific surface area, tunable structure and high stability. The integration of the concepts of high-entropy materials and MOFs can lead to high-entropy MOFs (HE-MOFs) and their high-entropy derivatives, which show rich structures and superior electrochemical performance and exhibit potential applications in the water splitting. This review summarizes the recent advances of the preparation of HE-MOFs and their high-entropy derivatives. Then, the research progress on the water splitting of HE-MOFs and their high-entropy derivatives is emphatically elucidated. Finally, the main challenges and the future development of HE-MOFs and their high-entropy derivatives in the fields of water splitting are prospected.