The present disclosure relates to a 3D display panel, including a lower substrate comprising a plurality columns of subpixels in which preset columns of subpixels serve as a buffer zone; a grating configured to allow images of one part of subpixels in the lower substrate to enter a left eye of a viewer, and allow images of the other part of subpixels in the lower substrate to enter a right eye of the viewer; a positioning unit configured to determine a first distance which the viewer moves, and determine whether any subpixel of non-buffer zone is shielded by the grating according to the first distance; and an adjusting unit configured to adjust the buffer zone when the any subpixel of non-buffer zone is shielded by the grating.