A three-dimensional hydrodynamic model has been presented in this study. The model is a three-dimensional coastal water model, in corporating a turbulence closure model to provide a realistic parameterization of the vertical mixing processes. The governing equations with boundary conditions are solved by an alternating direction implicit (ADf) finite difference technique with a total variation diminishing (TVD) scheme for solving advective equations. The model has been performed in the Belgian coastal wne (BCZ) which has very complex topography and strong current. The wmparisons between observed and computed results have been made. The results show that the main features in the BCZ can be well reproduces.