Achievement of a good performance in a Direct Numerical Simulation (DNS) of a particulate flow has been restricted to a low particle Reynolds number below a few hundreds due to the limitation of computational load by using a fine grid (Harada and Gotoh, 2008). Hence, in this study, to perform numerical simulations in higher particle Reynolds numbers, a Large Eddy Simulation (LES) by Smagorinsky model has been introduced into a solid/liquid two-phase flow model to reproduce a Sub-Grid Scale (SGS) turbulence. In addition, we have performed a numerical simulation of a settling process of graded particles in still water with and without LES to highlight the effect of turbulence. This model will be useful for prediction of diffusion of sediment cloud induced by construction of block mounds. Copyright © 2009 by The International Society of Offshore and Polar Engineers (ISOPE).