It was pointed out that there are some weak points on the transverse stability and turning ability in research on the development of Super High Speed Container Ship, so, in the 1 st report, we introduced vertical active fin under the bottom of the ship and reported its basic effectiveness by numerical simulation and model experiment in directional spectrum waves which was generated in the towing tank of Yokohama National University. In this report we introduced optimum regulator for the coupled control of rudder and vertical fin to improve stability and manoeuvrability. In order to carry out numerical simulation of the ship motion in directional following waves, we use experimental data of yaw and roll for estimating wave exciting force. Model propeller used for self propelled experiment was contra-rotating propeller in this time. We also refer to the reason of problem pointed out in the 1 st report that rolling motion became large even in the case of fin was fixed comparing to without fin case.