RNG κ-ε and VOF models in FLUENT software are used to simulate the flow field in the vicinity of a submerged spur dike. The result shows that the flow speed in main field is increased as a result of restraining by spur dike and a moderate backflow region with lower speed behind the dike. Backwater occurs near the dike so that the water level before the dike is increased while decreases behind, and then recovers along the channel. The simulation result coincides with the experiment and field observation and the calculated speed is close to the test data, which means that the model presented can be applied to the engineering calculation related to spur dike.