The present invention provides a movable partition wall assembly for adjusting distribution of space on either side of the wall for effectively utilizing room space. The movable partition wall assembly having a first member, a second member, a guiding mechanism, a driving means and rollers. The first member and the second member are secured together to configure enclosure therefrom. The guiding mechanism and the moving means for guiding and moving the enclosure in predefined orientation. The driving means is provided for operating the moving means through a transmission gear for moving the enclosure. The rollers are disposed on the lower side of the enclosure for reducing friction and sliding the enclosure on a floor of a room. Therefore, upon operating the driving means the moving means move thereby moving the enclosure in a predefined distance and direction, thereby enabling adjustment of space in the room on either side of the enclosure