We propose USN(Unilateral Spatial Neglect) treatment support system to promote attentional disengagement and movement based on Movable Slit : this technique is black out gradually stimuli of non-neglected side and expands gradually visible region to neglected side. We devised two systems as presenting method of the Movable Slit technique: Head-mounted system and Non-mounted system. Clinical testing using Head-mounted system for one patient show that Movable Slit allows patient to recognize the image of neglected side. The results suggest that patients using this system perhaps can recognize the stimulus of neglected side.