The experiment and the analysis by the use of finite element method were carried on to study the local strength of the deck plate subjected to the large wheel load such as that of ferryboat, car-carrier and Ro/Ro ship. In studying, it is assumed that those deck plates can be regarded to the rectangular plate loaded with partially distributed pressure. (a) Experiment The steel plates used in the experiment were square with side length 800 mm and 2.0, 2.3, 2.6, 2.9, 3.2 and 4.5 mm in thick. The tested plate was divided in three panels having 200 mm in width, 600 mm in length by supporting walls when the plate was fastened to testing apparatus. The behavior of the central panel was investigated. The plates were tested in two ways of loading. In the first, the load was increased continuously and in the second, as shown in fig. 8, the load was incresed under repeating the process combined of loading, unloading and reloading. We obtained the various behaviors of the panel, especially the pattern of the residual deflection after the load had been removed, and found the fact that the panel do not produce the collapsing due to forming the plastic hinge lines. (b) Analysis The calculated results were approximately consist with the experiment. It is shown that the behavior of the partially loaded panel can be predicted by finite element method. (c) Proporsal for design In can be considered that the deck plate subjected to large wheel load designed according to NK rule have the suitable scantling, but the method of designing on the basis of the actual behavior of the panel may be more reasonable than that assumming the plastic collapse.