To provide a method for manufacturing a self-supporting plain roof tile simplifying a metal mold structure to dispense with maintenance.

Tail side small end faces 33a, 33a of two hook protruding parts 33, 33 of a molding 2 are formed projecting outward from a tail 24 of the molding. In a surface mold 4, a forming surface 42a of a surface mold side face plate 42 for forming a tail side end face 3 is therefore fixed inclining at 91-98 opened with respect to the surface of a surface mold main plate 41. Further, since two small protruding parts 34 each, four in total, are formed on both sides of the hook protruding parts 33 of the tail side end face 3, the forming surface 42a of the side face plate 42 for forming the tail side end face 3, fixed to the surface main plate 41, is provided with small recessed parts 43 of corresponding recessed shape.