Morphing aircraft technology has recently gained attention of many research groups by its potential for aircraft performance improvement and economic flight. Although the performance of conventional control surfaces is usually compromised in off-design flight conditions, the morphing technique may achieve optimal flight performance in various operations by to adaptively altering the wing shape during flight. This paper aims to provide a comprehensive review on morphing aircraft/wing technology, including morphing mechanisms or structures, skins, and actuation techniques as element technologies. Moreover, experimental and numerical studies on morphing technologies applying those elemental technologies are also introduced. Recent research on these technologies are particularly focused on in this paper with comparisons between developments in Japan and other countries. Although a number of experimental and numerical studies have been conducted by various research groups, there are still various challenges to overcome in individual elemental technologies for a whole morphing aircraft or wing systems. This review helps for researchers working in the field related to morphing aircraft technology to sort out current developments for morphing aircraft.