An after-image prevention apparatus and method for a plasma display panel having a plurality of address electrodes and a plurality of scan and sustain electrodes arranged in pairs and in a zigzag pattern. An average signal level until the current frame from currently input picture data and an average signal level of each cell until the previous frame as stored in a memory section is calculated. The average signal level is compared with the picture data. An attenuation coefficient is generated corresponding to the difference between the average signal level and the picture data. The picture data is multiplied by the attenuation coefficient to output correction data, thereby preventing an after-image phenomenon on the plasma display panel.