PURPOSE: To improve productivity, and to reduce cost largely by extrusion- molding a long-sized roof tile raw material having an L-shaped cross section.

CONSTITUTION: A long-sized roof tile 1 having an L-shaped cross section is extrusion-molded, and cured and dried, and the roof tile raw material 1 is cut in fixed length. A creasing groove 4 is machined to the lateral piece 3 of the cut intermediate 2 having the L-shaped cross section. The lateral piece 3 and a longitudinal piece 5 are cut so that width is narrowed toward the ridge side and height is lowered toward the ridge side in the lateral piece 3 and longitudinal piece 5 of the cut intermediate 2, thus manufacturing a verge roof tile.