The present report shows the applicability of our numerical analysis method of wave propagation to the calculation of wave height distribution in a harbour of arbitrary shape where the boundary has an arbitrary reflection power. The principle is to solve the wave equations under given boundary conditions from an initial state with difference method.
　The validity of newly introduced calculation method to the boundary of arbitrary reflection power is confirmed by the application to the partial standing waves formed in front of a wall nad to wave diffraction by a semi-infinite breakwater of arbitrary reflection power. The comparison of calculated and experimental results to harbours of simple shape and examples of applicataion to harbours of practical shape are presented.