The water exchange capacity of artificial river system in the new town formed by reclamation in the coastal water is studied by means of water exchange tidal physical model test. The model test results show that the water exchange capacity of Lake Wood area with good hydrodynamic condition is best and except for the top of the curve and the north port, the water exchange capacity of meandering canal is better, while that of south port is the weakest. Through comprehensive analysis, it is found that water exchange capability is mainly depend on the unidirectional flow velocity and duration. Taking prototype current data as reference, it indicates that long time unidirectional flow exists in the artificial river system which is conducive to the water exchange of the artificial river system. The results of typical tide water exchange test point out that the Lake Wood, north port and Strolling Canal can meet the requirement of fulfilling one exchanging per week, but the south port which is semi-closed and weakest in hydrodynamic can’t meet the water exchange requirement. So it is suggested that the south port should be modified to meet the requirement of water exchange.