To manufacture a design block, wherein decorative coating is applied to the surface of a block in a desired decorative coating mode, without bringing about the deterioration of production efficiency.

A raw material is charged in an upwardly opened form 13 from the material supply box 16 horizontally movable above the form 13. When the material supply box 16 is moved so as to be retracted from the charging position of the raw material, a decorative coating material is added to the surface of the raw material charged in the form 13 in a desired decorative coating mode from a decorative coating mechanism part 25. Thereafter, the raw material in the form 13 is press-molded from above by a press mold 23 to mold the design block having decorative coating applied to the surface thereof in the desired decorative coating mode.