Organic electrochemical transistors (OECTs) have been hailed as highly sensitive biomolecular sensors among organic electronic devices due to their superior stability in an aqueous environment and high transconductance. At the same time, plasmon based sensors are known to provide high sensitivity for biosensing due to the highly localized plasmonic field. Here we report a plasmonic OECT (POET) device that synchronizes the advantages of OECTs and plasmonic sensors on a single platform. The platform is fabricated by a simple, cost-effective, and high-throughput nanoimprinting process, which allows plasmonic resonance peak tuning to a given visible wavelength of interest for versatile biosensing. With glucose sensing as proof, a five-times sensitivity enhancement is obtained for POET compared to a regular (non-plasmonic) OECT. Thus, the POET paves the way to a new paradigm of optoelectronic sensors that combines the inherent high sensitivity of OECTs and localized plasmonic field to sense a vast realm of biomolecules.