We have developed a high-resolution operational oceanographic system for the coastal waters of Korea. The operational oceanographic system consists of atmospheric and hydrodynamic models coupled with three-dimensional hydrodynamics, wave, sediment transport and water quality modules. We forecast the predicted results in the 72-hours base two times a day including sea surface elevation, currents, temperature, salinity, and waves etc. for the coastal waters of Korea. The predicted results are exported to the web-GIS based coastal information system for the real-time dissemination to the public. The operational system for the coastal waters of Korea uses operational model ROMS coupled with SWAN for the hydrodynamics and waves, WRF for the meteorological surface forcing, regional tide model NAO.99jb for the tides, and externally coupled CE-QUAL-ICM for the water quality. For the boundary condition the operational model is nested with another operational model ROMS which has been operated for the operational oceanographic system for the Yellow Sea.