The invention provides a flexible acquisition device and system of human body physiological signals. The collection of the human body physiological signals is achieved by collecting human body pressure fluctuations, the human body physiological signals can be collected without wearing the device, pressure signals are generated through the contact of teeth arranged on a lower sheet assembly or an upper sheet assembly with a piezoelectric film, even weak vibration signals generated by the change of only respiration, pulse or heartbeat can also touch the equidistantly and densely spaced teeth arranged side by side on the lower sheet assembly or the upper sheet assembly, and the timely pressure signals are generated through the contact of the teeth with the piezoelectric film. Compared with the traditional physiological signal acquisition device, the device can collect the weak vibration signals more accurately by collecting the signals through the contact of the teeth with the piezoelectric film, thereby improving the accuracy of collecting data.