The morphing aircraft is capable of actively adapting to changes in flight tasks, flight environments and flight states, thereby maintaining optimal performance in different tasks. Smart flexible deformable wing technologies, including the integrated flexible skin with good flexibility and load-bearing capacity, the high-power actuator, and the lightweight and high-reliability deformable mechanism, are crucial components of the morphing aircraft. In order to investigate smart flexible deformable wing technologies, based on the main wing deformation modes of the morphing aircraft, the focus and methods of researches on such key technologies of the deformable wing as the deformable skin, the drive technology and the deformable mechanism are analyzed. Additionally, the prospects of the aforementioned areas are identified.