Caofeidian harbor is a large size deep-water harbor currently under construction in the Bohai Bay, the eastern coast of north China. The construction began in 2003. The characteristics of tides and tidal currents in the Caofeidian area are analyzed with field data from comprehensive field observations from 2008 to 2010. The field observations and analysis show that the tide is the irregular semi-diurnal and tidal current is characterized as a type of reverse flow with moving west during flood tides and east during ebb tides. In general, the flood current is slightly stronger than the ebb current, and the strongest tidal current appears in the Caofeidian foreland, which is the predominant driving force to maintain the deep water depth.