To provide a partition wall structure allowing simple and quick forming work for a storage in a building site and partition wall, and facilitating partition and adjustment of installation position of the storage after installation.

The partition wall provided from the floor to the ceiling surface in the interior of a building is constituted by a casing 21 having the interior formed as a storage, and the top 27 of the casing is constituted by storage units 20, 22 having such a height as to secure a designated gap 23 for moving the casing in a space up the interior ceiling surface 29, and filling members 24, 26 filled in a gap between the storage unit and the ceiling surface in the installation position when the storage unit is installed in a designated position on the floor 10.