A spiral separator is one of the commonly-used gravity-concentration devices. It has been widely used in the mineral processing of coal. Also, it is used for the inexpensive pre-concentration of low grade ores. Spiral separator consists of an open trough that twists downward in helical configuration about a central axis. The aim of the present study is the simulation of the flow of water in spiral separators. The study is based on volume of Fluid (VOF) approach and turbulence modeling. The results focus on water-flow characteristics such as the depth of water as well as the turbulence intensity. The results demonstrated that the water depth and turbulence intensity on spiral trough increase smoothly outward. Predicted results are compared with the experimental findings from LD9 coal spiral. Comparison between the predicted and the measured values show good agreement and the most accurate turbulence model is RSM.