Microbial fuel cell (MFC) is a bioreactor which converts the chemical energy of organic compounds of chemical bonds to the electrical energy by catalytic reactions. In the current study a dynamic model is proposed, based on the direct transfer of electron for a two-chamber batch MFC at constant temperature, in which, lactate is used as the substrate, Shewanella as the microbial culture, and air as the input to the cathode chamber. The proposed model has many parameters. Some of these parameters are selected from the literatures and the others are estimated based on the experimental data. The required experimental data are prepared from a two-chamber MFC with working volume of 135 x 10(-6) m(3) for each chamber at two substrate concentrations of 5.0 and 7.5 kg m(-3). Three kinetic models known as Monod, Backman, and Tessier are used for describing the microbial specific growth rate. The results show that the better prediction of substrate concentration can be observed by using a Monod model (R-2 > 0.97). The predicted voltage and current of the MFC by the proposed model have good agreement with experimental data. (C) 2016 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.