Drag reduction in micro/nanofluidic systems is an important issue. The effect of boundary slip and electrical double layer (EDL) induced by surface charge on the pressure-driven flow in micro/nanochannel has been widely studied. However, change in electrical conductivity as a result of ionic redistribution caused by surface charge, which can affect the EDL-induced electrical force exerted on the flow, is often neglected. In addition, the effect of surface charge on the slip length is not considered. In this work, a model incorporating the effect of surface charge on electrical conductivity and slip length was developed to investigate the effect of boundary slip and EDL induced by surface charge on the volumetric flow rate and skin friction coefficient. The underlying mechanisms for the results regarding the effect of slip and surface charge on the flow were analyzed. (c) 2012 Elsevier Inc. All rights reserved.