With a ship model of single screw high speed container ship of L/B=8, resistance and self-propulsion tests in regular and irregular head waves were carried out in the Experiment Tank of Osaka University. The experimental results of ship motions and resistance increases in regular head waves are compared with the results obtained from the theoretical calculations and also with those obtained for a container ship model of L/B=6.89 in the first report. The self-propulsion factors in regular head waves are analysed by assuming that the mean characteristics of a propeller are identical with those in still water. The significant amplitudes of heave and pitch and the mean increases of resistance, propeller thrust, torque and revolution measured in irregular head waves are compared with the predicted values by the linear superposition technique. Furthermore, the effects of mean wave period and significant wave height of irregular waves on the ship motions and the mean increases of resistance, propeller thrust etc. are investigated.