In this study, a novel quartz crystal microbalance (QCM) based on the modification of paraoxonimprinted polymer onto a QCM with a high selectivity and sensitivity has been developed for the determination of paraoxon. The QCM sensor has characterized using AFM and ellipsometer. The performance of the QCM sensor has evaluated and presented good reproducibility, shorter response time (20 min), wider linear range (0.02-10 mu M) and low detection limit (0.02 mu M). The results have shown that the selectivity of QCM sensor has found as being very high in the presence of parathion which is similar in structure with paraoxon. (C) 2013 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.