An image apparatus for processing 3D images and a method for controlling thereof are provided. The apparatus includes: a display unit onto which data is scanned; and a display driver which makes left frame image data and right frame image data be alternately scanned onto the display unit and makes removal data for removing the left frame image data or the right frame image data be scanned onto the display unit between the left image frame data and the right image frame data. Therefore, while an image is being scanned, a residual image of the previous frame image is not displayed.