Abstract: Using the quasi-harmonic method,we anchored at the three stations in the Liaodong Bay for 25 hours in September, 2009 for study of the tidal current characteristics. The harmonic coefficients of the O₁, K₁, M₂, S₂, M₄, MS₄ tidal current constituents are calculated for their north and east components. The tidal current elliptic factors are also computed. It demonstrates that the tidal current in the study area is a regular semidiurnal tidal current mainly in NE-SW reciprocating movement. The maximum possible flow rate is between 70cm/s and 120cm/s. In general, the velocity decreases gradually from surface to bottom. The north component of O₁, K₁, M₂, S₂, is generally stronger than the east one. The bottom tidal current generally flows earlier than the surface tidal current. The maximum velocity is also earlier at the bottom than that in the surface. The ratio of shallow water tidal current constituent to total current is very low.