This paper presents a flow-structure interaction simulation-aided morphology optimization of harbor seal whisker, for generating a whisker-like structure which could possibly perform better in minimizing vortex-induced vibrations (VIVs) when subjected to steady flows. We also propose a whisker-inspired flow sensor design which features a 3D printed polymer model of the optimized seal whisker mounted on a 3D-printed double cantilevered sensor base consisting of graphene nanoplatelets piezoresistors at the hinges. The designed flow sensor’s performance in sensing the flow velocity and its sensitivity to the external force are demonstrated by computational fluid dynamics simulations and proof-of-concept experiments, respectively