Due to the wide flammability range and low ignition delay of Hydrogen, it can burn rapidly and generate a large amount of thrust. It is for this reason alone that many researchers have promoted hydrogen as a potential fuel in scramjet engines. As H-2 is also environmentally safe and clean and can be produced from abundant sources, several researchers across the globe support the use of H-2 fuel. However, its lower volumetric energy density and higher flammability range also have an adverse effect in on-board storage system for aircraft propulsion applications. This review gives a brief representation of Hydrogen fueled scramjet engine as well the challenges associated with H-2 fuel. Additionally, the advantage of hydrogen as a fuel as compared to other hydrocarbon fuel is also discussed here thoroughly. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.