High-efficiency decomposition technology for volatile chemical warfare agent sarin was developed using a dielectric-barrier discharge (DBD). The power consumptions of the developed device for which the gap lengths of the plasma-generation sites were 1.0-2.0 mm, were found to be 22-27 W, respectively. The DBD driven sarin-decomposition amount per unit time and the decomposition efficiency in the optimized condition were obtained to be 2.05 x 10(-3) mg/s and 1.38 x 10(-4) mg/W, respectively, measured by ion mobility spectrometer. Sarin-decomposition products were investigated using a gas chromatography-mass spectrometry with tert-butyldimethylsilylation derivatization, indicating that isopropyl methylphosphoric acid (IMPA), methylphosphoric acid (MPA), and phosphoric acid (PA) were generated during sarin decomposition by DBD. The decomposition efficiency at 37 W decreased by 41% molar concentration compared with that at 15 W, but the production levels of IMPA, MPA and PA were changed from 10.0%, 41.5% and 3.9% to 7.2%, 21.3% and 6.4%, respectively.