A method of manufacturing a compressed wood product includes applying a compressive force to a wooden piece in a water-vapor atmosphere having temperature and pressure higher than those of atmospheric air to deform the wooden piece into a three-dimensional shape having a curved surface; placing an attachment for forming a pattern at a desired position on a surface of the wooden piece after applying the compressive force; and applying a pressure to the attachment and the wooden piece while heating the attachment and the wooden piece in the atmospheric air to shape the wooden piece into substantially the same shape as the three-dimensional shape and to firmly fix the attachment to the wooden piece.