To provide a staircase room facilitating the fitting work of a corner bead and a baseboard.

This staircase room includes a baseboard 40 provided along an inner wall face 30 and a corner bead 50 abutting on treads 12 and risers 13 between a floor surface 20 kept in contact with the lowermost section of a staircase 10 an the inner wall face 30 of the staircase room 1. The height dimension D of the baseboard 40 is made smaller than the height dimension H of the riser 13, and the baseboard 40 is continued at the intersection portion between the baseboard 40 and the parting edge 50. Since the height dimension D of the baseboard 40 is made smaller than the height dimension H of the riser 13 and the baseboard 40 is overlaid at their intersection portion, the arrangement of the lowermost portion of the staircase 10 can be simplified, and the fitting work of the parting edge 50 and the baseboard 40 can be facilitated.