To provide a baseboard device for a scaffold, which can be inexpensively manufactured by virtue of a relatively-simple structure, and which can be easily operated.

This baseboard device 10 for the scaffold is used by being attached to an existing material 14 which is made of a scaffold material or a treadboard of a temporarily-assembled base. The baseboard device 10 includes: a long baseboard body 11; a plurality of mounting bracket 13 which are mounted with a gap on the one side of the baseboard body 11, and the lower portions of which have U-shaped bent portions 12, respectively; an auxiliary fitting 16 which is provided in midway of the mounting bracket 13 and engaged with the upper end 15 of the existing material 14; an operation member 19 which has a horizontal shaft 17 passing through the U-shaped bent portions 12, and which has the base end of a lever 18 connected to the horizontal shaft 17; and a piece material 20 which is fixed to the horizontal shaft 17, and which clamps and unclamps the existing material 14 above by turning the operation member 19.