In this paper, an analytical approximation for the evaluation of the pore pressure and effective stresses in marine sediments under combined wave and current loadings is derived. Unlike previous investigations, non-linear interactions between waves and currents are considered in this study. An analytical solution for the wave-current induced oscillatory soil response in marine sediment is presented first. Based on the proposed analytical solution, a parametric study for the liquefaction potential will be carried out. Parametric study results indicate that the influence of current and non-linear waves on the maximum liquefaction depth is significant. (C) 2012 Elsevier Ltd. All rights reserved.</p