The article discusses the growing energy demand and environmental challenges faced due to the overuse of fossil fuels, leading to the exploration of renewable and green energy sources like hydrogen, hydropower, and solar energy. It emphasizes the role of electrochemical energy storage and conversion technologies, including rechargeable batteries, fuel cells, and hydrogen evolution devices, in addressing these challenges. The focus is on the development of advanced materials, particularly high-entropy compounds (HECs), for enhancing the performance of energy storage and conversion systems. HECs, a new type of materials, have garnered attention for their unique structures and properties not typically found in traditional materials. They offer benefits like high specific capacity, catalytic activity, and stability, making them ideal for various applications. The article highlights the peculiar effects of HECs, such as the high-entropy effect and cocktail effect, which contribute to their excellent performance in energy-related processes. It also stresses the need for a systematic review of recent progress in HECs for energy storage and conversion to advance their development and application in the field of material science.