This study aims to identify the formative features of inflatable fashion that has changed its form or fulfilled specific functions by inserting air between fabrics or between clothes and the human body. Images of inflatable fashion images after the 1990s were collected from the literature and internet data and were analyzed based on the formative features of inflatable design. Through this analysis, it was determined that there were four formative features of inflatable fashion: First, inflatable fashion has functionality. General fashion also has functionality, but inflatable fashion has expanded functionalities such as an air bag effect or insulation due to injected air. Second, the formative potential. Inflatable fashion can be changed into different forms depending on the amount of air injected. Light-weighted air holds up the material of the clothes. So new forms that are different from conventional fashion, which gives inflatable fashion its formative potential, can be suggested. Third, aesthetic expansion. Inflatable fashion when its volume is expanded expresses the beauty of scale, or expresses a voluptuous beauty when part of human body is exaggerated. Fourth, it has an unconstructive characteristic. Space that is visible due to the transparent material of inflatable fashion expresses the intention of the designer to fulfill an unconstructive concept. In conclusion, the formative features of inflatable design have formative significances : practicality, aesthetic significance, semantics and technical significance.