Conducting poly (2,6-dimethoxynaphthalene) (PDMN), a novel fluorescent polymer was electrochemically synthesized in boron trifluoride diethyl etherate (BFEE) containing additional concentrated sulfuric acid via direct anodic oxidation of 2,6-dimethoxynaphthalene (DMN). The oxidation potential onset of DMN in this medium was 0.43 V, lower than other electrolyte media. PDMN films showed good electrochemical behavior and thermal stability. The structure and morphology of the polymer were investigated in detail. Fluorescent spectra indicated that the electrochemically polymerized PDMN was an excellent blue light-emitting material. The insoluble PDMN film deposited on the indium tin oxide glass was used to develop a sensor for the determination of imidacloprid based on the fluorescence quenching of PDMN. The interaction of imidacloprid and PDMN was investigated by electrochemical techniques. The fluorescent intensity of PDMN has a good linear relationship with the concentration of imidacloprid on the surface of PDMN in the range of 4.994 x 10(-1) to 2.557 x 10(2) mu g/mL with a detection limit of 3.093 ng/mL. The sensor based on PDMN films showed high recognition ability for imidacloprid and will have more potential applications in the industrial or environmental and healthy fields. (C) 2013 The Electrochemical Society. All rights reserved.