ABSTRACT: A new berth system with a floating quay is developed to greatly ehance loading and unloading capability of the existing land based berth. The floating quay can supply functions of not only both side loading/unloading but also direct transshipment to feeder ships, without significant civil works. In addition, the floating quay is designed as a mobile quay to improve the quay productivity. Applying the floating quay system to the west terminal of Busan New Port ofKorea, it is shown from a numerical simulation that the quay is dynamically workable and stable in the prevailing and design storm wave conditions, respectively. When the both side loading/unloading system is adopted by using the floating quay, the terminal productivity is increased by 212% comparing with the present land based berth using 5quay cranes. The B/C ratio of the new berth system at the West Terminal of Busan New Port is evaluated as 1.55 for asuper-large container ship operated with one land based berth. It appears that the HQW is to be the technically and economically feasible system for a very large container ship.