An organic field‐effect transistor (OFET) is the representative amplification device showing a switching profile by applying a gate voltage, which indicates the potential as a chemical sensor device in combination with appropriate molecular‐recognition materials. In contrast, the realization of OFET‐based chemical sensors for real‐sample analysis is limited owing to the instability of organic semiconductive materials under ambient conditions and the difficulty of the designs of molecular‐recognition materials. Methodologies and actual approaches to maximize the potential of the OFETs as chemical sensor platforms based on fusion technologies between organic electronics and molecular‐recognition chemistry are described in this review.