The present study investigated the residual effect of gliding arc discharge (GAD) treatment on the inactivation of bacteria in a large volume of water (i.e., 20 L). Pure water and air were introduced to GAD separately, and then both the gas and water treated by plasma were sent to bacteria-containing water. Water contaminated by Escherichia coli (E. coli) was first treated by GAD for 10, 13 and 16, and 25 min and then stored for the next 4 h, during which time the E. coli concentration and pH were measured. In general, GAD produced the strong anti-microbial properties, a phenomenon which increased with plasma treatment time. More specifically, E. con was partially inactivated (i.e., approximately 2.7-log reduction) with 16-min plasma treatment. However, E. coli was almost completely inactivated (over 99.9% with 5-log reduction) during the subsequent 4-h storage period, a phenomenon that was attributed to the residual effect of the plasma treatment. The optimum plasma energy cost of the GAD treatment to inactivate E. coli in 20-L water in the present study was found to be approximately 0.57 kJ/L per 1-log reduction. (C) 2014 Elsevier Ltd. All rights reserved.