The bigger the size of ship becomes, the more complicate questions arise on the hull construction. The gunwale connection in the mammouth ship is one of the most grave questions, because of the poor purchasability of the big size gunwale angles, the hard workmanship on the riveting of large diametres, and etc. As the countermeasures for the above-mentioned questions, the Tee-section or angle built-up by welding, or else the rounded gunwale, were already proposed. The authors examine the current practices of the gunwale connection in the mammouth ship and propose a new type of welded gunwale, “L-gunwale”, as the most promising.