Abstract: Disclosed herein are an apparatus for driving a plasma display panel in which the capability to represent the gray scale can be improved, and method thereof. The apparatus includes an inverse gamma control block for performing an inverse gamma correction process on input data received from the outside by using two or more gamma values, and a select unit for outputting one of two or more output data on which the inverse gamma correction operation is performed, which is outputted from the inverse gamma control block. Therefore, the capability to represent the gray scale can be improved. Furthermore, an error diffusion pattern and pseudo noise can be reduced and the picture quality can be thus improved.