Abstract: The flexible wearable respiratory sensing and monitoring system includes flexible respiration sensors and integrated circuits, containing multiple functions of signal sensing, storage, transmission and processing. The system has the characteristics of small size, high accuracy, simple operation, and low cost, which can be widely used in practice and the application range is larger than that of polysomnography, commonly used in clinical field. The respiratory sensing system can meet the needs of long-term monitoring and early diagnosis of respiratory diseases. Firstly, the working principle of the respiration sensor is simply introduced. Then, the respiratory monitoring systems are divided into two categories, direct monitoring and indirect monitoring system, based on the implementation methods of systems. Specifically, the different monitoring locations and working modes are discussed. Finally, a brief summary and prospect of the flexible wearable respiratory sensing and monitoring system are proposed to provide a reference for the interested researchers.