Jebel Ali Harbor in Dubai is one of the largest man-made ports in the world. Due to its bottle-like nature, it is anticipated that little mixing or wave action occurs within the harbor; however, no study has been conducted to investigate the harbor's hydrodynamic regime. In this paper, the circulation pattern in Jebel Ali Harbor is presented. The vertical profile of temperature and salinity shows that the harbor water is fairly well-mixed, justifying the use of a depth-averaged, 2-D model. Modeling the hydrodynamic pattern of Jebel Ali Harbor was carried out using MIKE21 model. Although tide is the main driving force of circulation in the harbor, wind and Coriolis forces were taken into account in the simulation. Simulation results showed that both dead and eddy zones exis. As the harbor receives treated wastewater from several industries located in the area, flushing out of a conservative tracer by the advection-dispersion process was also simulated using MIKE21. Results revealed that the flushing time of a conservative tracer from the harbor varies significantly with the discharge location. Simulated results showed that understanding the hydrodynamic regime of Jebel Ali Harbor is useful for selecting the location and time for discharging tracers into the harbor. Copyright 頲008 AEHMS.