A simplified isotropic numerical treatment for solving the anisotropic electron transport phenomenon in PEM fuel cells has been proposed. In order to maintain appropriate lateral current distribution, the in-plane electronic conductivity in the catalyst and gas diffusion layers is utilized, while an extra contact resistance is added between the gas diffusion layer (GDL) and the current-collecting land to compensate the reduced through-plane electronic resistance. This simplified method is also applicable for solving the anisotropic heat transfer phenomenon in PEM fuel cells, and it improves numerical convergence and stability in three-dimensional large-scale simulations. (c) 2006 Elsevier B.V. All rights reserved.