Considering the natural conditions of Chinese waterways and the majority of ports, it is necessary to develop a shallow draft full form ship for economic operation. The ratio of breadth to draught is well beyond the conventional practices. so that the strength in the sea way should be under special consideration. In this paper the results of a segmented elastic-keel model test in both regular and irregular waves are presented. In addition, the results calculated by means of 'strip theory' are also given. This research may be useful for designing of similar type ships.