In the paper, a novel ordered mesoporous carbon/cobalt oxide nanocomposite (OMC-Co) was easily synthesized. After encapsulating cobalt oxide nanoparticles in the wall of the ordered mesoporous carbon (OMC), the mesostructure of the nanocomposite material remained highly ordered and intact. For the first time, OMC-Co material was used to modify the glassy carbon (GC) electrode, and the obtained OMC-Co/GC modified electrode showed strong electrocatalytic properties towards glutathione (GSH). The use of OMC-Co film to mediate the GSH oxidation exhibited remarkably strong and stable electrocatalytic response compared to that seen at OMC/GC electrode. These results showed that the electrocatalytic properties of CIVIC could be improved when the cobalt oxide nanoparticles were incorporated into this new material. A sensitive GSH sensor was developed based on the OMC-Co/GC electrode, which showed a high sensitivity and a remarkably low detection limit. Moreover, OMC-Co/GC modified electrode can be used for selective amperometric determination of GSH in the presence of glucose, dopamine (DA) and uric acid (UA). (C) 2009 Elsevier Ltd. All rights reserved.