Abstract: Underwater detectors are widely used in marine engineering equipment, which have important functions such as sensing underwater environment for ships and submarines. The currently applied sensors are faced with restrictions such as short detection distances, high power consumption, and insufficient signal-to-noise ratio, by which their large-scale applications are limited. For a long time, bionics research has provided a lot of innovative inspiration for the design of marine engineering equipment. Researchers found that the predation and hedging behavior of harbor seals depends on the perception of the underwater environment by the special structure of their vibrissa. In this paper, through the study of the vibrissa structure, a vibrissa-shaped underwater detector was designed and manufactured, and its excellent underwater target detection capability was verified by experiments conducted in a water tunnel. In the experiment, different working conditions such as angle, incoming flow velocity and detection target position were studied. The spectrum analysis of the signal collected by the detector was used to master the working rules of the vibrissa-shaped detector.