Ballast water for vessels is significant to prevent their stability and propulsion performance losses, which are caused by their light-draught. However, the International Maritime Organization (IMO) adopted International Convention for the Control and Management of Ships' Ballast Water and Sediments in 2004, because of avoiding its environmental impact.Then, in order to solve this problem, new hull forms are being designed, which use a small amount of ballast water or don't need ballast water. For example, one of new designed hull has shallow draught and wide breadth. Such a type of hull may show different roll characteristics from the conventional vessels.In this study, for a wide breadth and shallow draft vessel, its roll characteristics seas are investigated experimentally. The results show that its roll natural period is changed by its roll amplitude and its roll resonance occurs in different wave period for different wave height. Then the adaptation of the estimation methods of roll amplitude in resonance wave, which are proposed by International code on Intact Stability 2008 of IMO (2008 IS code), for this shallow draft vessel is also investigated. As the results,it is indicated that the parameter identification technique (PIT), which is one of recommendations, is better method to understand roll response of the object hull form.