This study analyzed the hydrodynamic flow behavior on a standard ogee spillway with pier by using FLOW-3D. The simulation results were compared with the experiment data of U.S. Army Corps of Engineers - Waterways Experiment Station (WES) and also compared with 2-dimensional simulation results on a spillway without pier. In particular, the characteristics of the distribution of the overflow nappe and pressure in a spillway with pier were investigated in detail. As for the results of the simulation on the flow rate, overflow nappe, and pressure, although there were a few differences in the experiment results of WES, they were identical in most cases in terms of trend. Summarizing the major flow behavior in a standard ogee spillway with pier, first, the water stage at the center line of the bay was higher than that at the side of the bay along the pier. Second, when the water head was larger than the design head of the spillway, at the upstream area of the weir crest, the absolute magnitude of negative pressure occurred highest at the side of the bay along the pier. On the other hand, at the downstream area of the weir crest, the absolute magnitude of negative pressure occurred highest at the centerline of the bay.