Although shipping was not included in the final text of the Paris Agreement in 2015, IMO (International Maritime Organization) adopted the EEDI (Energy Efficiency Design Index) and the EEOI (Energy Efficiency Operational Indicator) to control climate change and also to reduce gas emission from ships. Accurate prediction of added resistance in waves is essential to evaluate the minimum fuel consumption of a ship in a real sea state. In this paper, the added resistance and motions of a KCS (KRISO Container Ship) with rudder were calculated using a commercial CFD program, STAR-CCM+. Wave forcing was used to generate the waves in the numerical domain, in which no extra wave generation and damping zones were produced. DFBI (Dynamic Fluid Body Interaction) was used for the motions of the KCS with rudder. In this study, five (5) regular head waves from a short wavelength to a long wavelength based on the LPP were considered. Finally, added resistance and the heave and pitch motions of the simulation were compared with experimental data. Simulation and experimental data were in qualitatively and quantitatively good agreement.