In order to achieve the continuous and dynamic monitoring of physiological signals, such as the pulse wave, the respiratory wave and the blood pressure, a wearable health monitoring body area network system based on piezoelectric film sensors was made. Using the sensors attached into the stretchy fabric (For example, belt and wristband), the system can receive physiological signals such as pulse wave and respiratory wave. A condition recognition algorithm was proposed to distinguish conditions such as lying, standing, sitting, walking, running and sleeping by analyzing the geometric features of the respiratory signals received from piezoelectric film sensors. Taking advantage of the relationships between pulse wave translation time and blood pressure to calculate diastolic blood pressure and systolic blood pressure of user, the pressure-free blood pressure measurement was achieved. The nodes communicated with each other through Bluetooth. The data were displayed on the wearable display devices and mobile devices. The system realized continuous and dynamic monitoring of physiological signals, such as the pulse wave, the respiratory wave, the blood pressure.