Depleting energy resources, global warming and environmental problems associated with conventional fuels are serious global challenges of the modern world. The substitution of conventional energy resources with more efficient and sustainable resources is inevitable. In this scenario, hydrogen (H 2) has emerged as the ultimate choice due to its superior characteristics such as low carbon emissions, cleanliness, and efficiency. However, for the successful implementation of making H 2 as the next-generation fuel source, the hurdles of production, separation, and storage of H 2 should be resolved. This paper summarizes the issues and challenges in the separation of H 2 gas from various production streams by using available separation technologies. Different types of H 2 separation technologies, including membranes, adsorption processes, metal hydrides, and cryogenic separation technologies, have been …