he sensory organs are essential for many animals, especially for those creatures living underwater. In this paper, a surface four-electrode PVDF piezoelectric fiber biomimetic flexible sensor was designed and fabricated using polyvinylidene fluoride(PVDF) as the material, imitating the tentacles of aquatic animal seals. The excitation source is used to test the performance of the prepared sensor, including outputting different waveforms to test the perception of different excitations, the perception of hydrodynamics and the perception of the directions of underwater moving objects. The experimental results show that the sensor has good sensing performance for different excitations; the speed detection limit reaches 0.15 mm/s, and has good directional detection ability. It has great application prospects for the underwater situation perception.