The present invention relates to a plasma display apparatus and, more particularly, to a plasma display apparatus in which the ability to represent gray levels can be improved and halftone noise can be reduced by improving a plasma display apparatus and image processing method thereof. According to the present invention, the plasma display apparatus includes a motion detection unit that detects motion information of input image signal data, and a halftoning unit that halftones the image signal data by using at least one or more of a dithering method and an error diffusion method according to the motion information received from the motion detection unit.