Wave generators with small segments have been developed to reproduce directional random waves in experimental basins. The multi-face directional random wave maker with generator faces along the three sides of a basin is proposed to enlarge the effective test area in which target directionality is reproduced. Applicability and reproducibility of the multi-face generator is experimentally investigated.
　Numerical simulation is carried out to propose the best arrangement of multiface generator.
　The following main conclusions are derived;
1) Uniform distributions of wave heights and propagating angles are formed in the whole area of the multi-face generation basin except an oblique line from the generator corner.
2) Target wave directionality is reproduced in the whole area of the multi-face generation basin.
3) Applicability of the multi-face generator is able to be raised by installing a curved part at the corners.