Abstract: A method and apparatus for displaying a gray scale of a plasma display panel, by which generation of a pseudo contour upon expression of a gray scale with respect to a moving picture is prevented when a picture is displayed on a plasma display panel. The method can prevent generation of pseudo contours of dark lines (or bright lines) so that a temporal inconsistency appears as spatial inconsistency, at a portion of a moving picture in which gray scale changes are subtle, when expressing a gray scale by temporal duplication of light emission using the after-image effect of vision.