Bodily responses and elastic distortions of full-form ship advancing in short head waves are analyzed analytically for a ballast-loaded large tanker. In order to derive the wave exciting force acting on ship hull, a method for analyzing the diffraction problems of a blunt ship advancing in short head waves are presented. The Unified Dynamic Theory of ship responses in waves developed by Bishop and Price is applied for the analyses of motions and flexural vibrations of ship hull. Because that there are no complete data sets available for actual ship structures, a hypothetical model of a ballast-loaded large tanker is introduced for the numerical analysis. Some discussions are made by using the numerical results.