This paper comprehensively reviews the research progress and engineering applications of the Vacuum Bag Only (VBO) molding technology for Out-of-Autoclave (OOA) prepreg in aviation composite structures. First, it examines the development trajectory and current research status of this technology both domestically and internationally. The paper then compares this method with traditional autoclave molding and liquid molding techniques, highlighting its unique advantages. Furthermore, it delves into the molding mechanism, key process parameters and application cases of OOA prepregs in aviation structures. Performance testing and cost analysis demonstrate the advantages and potential of this technology in manufacturing aviation composite components. Ultimately, the paper summarizes the current state of the technology and explores its future development directions. The OOA prepreg VBO technology has demonstrated significant cost-saving and efficiency-enhancing advantages in the manufacturing of aviation composite components. It enables the production of parts with excellent mechanical properties while reducing equipment investment and processing costs. As a result, this technology is expected to play an increasingly important role in the field of aviation composite material structures and to drive innovative advancements in the aviation manufacturing industry.