Traditional postharvest fruit quality control relies on physicochemical indicators, rigid sensors, and complex instruments for monitoring, detection, or prediction. However, this approach has several limitations, such as time-consuming procedures, destructive techniques, and low monitoring accuracy. In this paper, we propose the use of flexible sensing technology as an alternative to rigid sensors in postharvest fruit quality monitoring and long-term environmental signal monitoring. The paper examines fruit quality characterization parameters, analyzes the performance requirements of flexible sensors in various cold chain scenarios, and explores emerging applications of flexible technologies in fruit quality control at internal, external, and environmental levels. The study demonstrates that the exceptional stretchability and biocompatibility of flexible sensors offer promising platforms for real-time fruit quality monitoring and detection. Moreover, the use of multi-scale flexible sensors enables information sensing in confined spaces. Combining these sensors with machine learning algorithms, wireless sensing technology, and intelligent devices like manipulators effectively enhances monitoring accuracy. Finally, the paper discusses future directions for improvement, including advancements in materials and processes, passive sensing methods, and integration with other smart technologies or devices.