To mount a rail for fittings precisely and rapidly to a mount surface of a lintel, sill, etc.

In the structure for mounting rails for fittings, for erecting a door board 7, there are provided a top rail 1 to be fixed to a top fixing part 3 comprising a lintel, a top frame body, a ceiling, etc., and a bottom rail 6 to be fixed to a bottom fixing part 12 comprising a sill, a bottom frame body, a floor surface, etc. And at least one narrow straight grooves 16, 16a is provided in the longitudinal direction in each of mount surfaces 4, 13 of the part 3, 12, to which the rails 1, 6 are mounted. Protrusions 15, 15a are formed respectively on mount surfaces 2, 11 of the rails 1, 6 in the longitudinal direction corresponding to the grooves 16, 16a to mount the rails 1, 6 on the parts 3, 12 respectively by fitting the protrusions 15, 15a into the grooves 16, 16a respectively.