Rotating detonation is regarded as an innovative combustion mode. A detonation wave is formed by the initiation of a mixture of fuel and oxidizer. The wave propagates continuously and rapidly in a rotating manner inside the combustor. Distinct advantages are possessed by this combustion mode, including high combustion rate, high thermal cycle efficiency, compact structure and self-pressurization. Research progress of the rotating detonation engine (RDE) is systematically summarized in this paper. Three core aspects are mainly emphasized. The first aspect is the design and optimization of the combustor, including the injector structure and various configurations such as annular, disk, cavity and recessed cavity. The second aspect is the research status of integrated systems of RDE with nozzles, turbines and ramjet components. The third aspect is detonation initiation and propagation characteristics of gaseous and liquid fuels. Key technical bottlenecks in this field are also analyzed. Precise and innovative combustor configuration designs are demanded to improve adaptability under variable working conditions. In multi-fuel systems, difficulties in efficient mixing and stable self-sustaining propagation of detonation waves need to be overcome. Reliable and rapid development of the detonation process is ensured. Theoretical and practical references are provided for the engineering application of RDE technology.