Here, we developed highly sensitive piezoelectric sensots,in which flexible membrane components were hatitioniously integrated. An electrospun nanofiber mat of poly(vinylidenefluoride-co-trifluoroethylene), was sandwiched between' two elastomer sheets with sputtered electrodes as an active layer for piezoelectricity. The developed sensory system was ultrasensitive in response to various microscale mechanical stimuli and able to perceive the corresponding deformation at a resolution of 1 mu M. Owing to the highly flexible and resilient properties- of the components, the durability of 'the device was sufficiently stable-.'so that the measuring performance could still be effective under harsh conditionsof repetitive Stretching and folding. When employing spin-coated: thin 'elastomer filins, the thickness of the entire sandwich architectute Could be less than 100 mu n, thereby achieving sufficient compliance of mechanical deformation`.to accommodate artery skin motion of the heart pulse. These skin-attachable film- or sheet-type mechanical sensors with 'high-flexibility are expected to enable various applications in the field of wearable devices, medical monitoring systems, and electronic skin.