A computer program for the calculation of heaving and pitching motions of ships in regular waves, by the strip method, was developed by Fujii and other. The authors tried to extend the program to calculate longitudinal wave bending moments and shearing forces in regular waves, not only at midship but also various position along the ship length. The fundamental equation of motion is based on Watanabe's theory, and added mass coefficients and damping coefficients are obtained by the Tasai's method. The formulae of wave bending moments and shearing forces are those which are proposed by Fukuda. Some calculations on a gigantic tanker both in regular and irregular head waves are carried out and the results were compared with the requirement of a classification society.