Single-electron transistor drain current is studied as a function of the temperature. A current conduction model based on the physical properties of the tunnel junctions is proposed to explain the discrepancies observed at high temperature between the experimental data and Monte Carlo simulations. The extension of the model includes a thermionic and a field assisted emission component. A demonstration of this approach is presented for a metallic single-electron transistor characterized up to 430 K. (C) 2009 Elsevier Ltd. All rights reserved.