Abstract: Institute of Turbomachinery, Xi'an Jiaotong University, Xi'an 710049, Shaanxi Province, China In the context of global energy transition and carbon reduction and emission mitigation, hydrogen energy has been widely regarded as a crucial component of zero-carbon energy system by the international community. Hydrogen gas turbines, serving as essential support for decarbonization of power system and construction of novel multi-energy complementary system, have emerged as a critical pathway for deep decarbonization of future power system due to the advantages of zero-carbon emission potential, flexible peak-shaving characteristics, and high coupling capability with renewable energy sources. Three aspects were systematically reviewed and summarized: hydrogen-blended fuel combustion and emission characteristics, advantages of hydrogen gas turbines, and cascade aerothermal performance of hydrogen gas turbines. The analysis addressed the difficulties and challenges of efficient and stable combustion of carbon-based fuels blended with hydrogen or pure hydrogen fuel, thermal protection design of turbine cascades in high-temperature and high-humidity operation conditions, and organization of cascade film cooling in strongly fluctuating flow fields. Finally, considering the current research status of cascade aerothermal performance of hydrogen gas turbines, design concepts and prospects were proposed for efficient cascade film cooling of hydrogen-fueled turbines.