In this paper a study on prediction of the wave resistance performance of a very large crude oilcarrier(300K VLCC) was taken into account according to the changes in L/B/T. The wave resistance ofthe ship was calculated using the potential based panel method in which exact nonlinear free surfaceboundary conditions and the trim and sinkage were considered. The panel cutting method wereimplemented to generate the hull surface panel and the free surface panel were generated using thevariable free surface method. The numerical analysis was carried out according to the 12 different ships. The wave resistance coefficients and the wave patterns of the 12 different ships were compared with eachother. As a result the wave resistance of a ship was found to be significantly affected in L/B than T.