The accelerating development trends of world aeropropulsion technology will be persistent in the 21st century and some revolutionary changes will occurr. With the breakout of some key technologies, the traditional gas turbine engine will be improved greatly. The achievements of power for ultra-supersonic flight vehicles would result in a new generation of aviation with the application of supersonic combustion screamjet and combined engine as turbine based combined cycle (TBCC) engine and rocket based combined cycle (RBCC). With the innovation of new concepts and scheme, some new concept engines will be invented and applied, such as the pulse denotation engine (PDE) and super micro-engine based on micro-mechanical-electron technology. Instead of the conventional hydrocarbon fuel, some new energy will be applied in future advanced aeroengine. The developments of aeropropulsion technology in the new century will promote the progress of civilization and human being society greatly just as in the past 100 years.