This report presents an experimental study investigating the dynamic pressure exerted on tank walls of ship by swashing internal fluid. The case, in which no obstacles such as swash bulkheads or deep girders existed in the tank, was reported already in the previous report. In this paper, the case, in swich a swash bulkhead was inserted at the center of the tank, was dealt with. In the present experiment, second to the experiment described in the previous report, the bulkhead was made of strips, and its breadth and the height of its center were changed systematically, in order to observe the influence of the bulkhead. From this experiment, we derived the experimental formula for the force acting on the end bulkhed and the swash bulkhead. In the third experiment, the swash bulkhead of the practical type were tested. The results of this experiment were compared with the ones of the second experiment, and experimental formula were reformed for the use in the actual swash bulkhead. From the above results, the effectiveness of the swash bulkhead was examined as follows. At first, with a view to observing the burden of the end bulkhead, the maximum waterhead which could occur on the end bulkhead was calculated by the experimental formula, and the extent of reduction of maximum waterhead by the insertion of the swash belkhead was examined. Then the limit percentage of the swash bulkhead, which is useful for the reduction of the burden of the end bulkhead was calculated for the arbitrary tank length. Then, in view of minimum weight design, the effectiveness of swash bulkhead was exmined, considering the total force on the end bulkhead and the swash bulkhead.