An afterimage detection device includes a downscaling unit that downscales an input image at a preset ratio, an image accumulation unit that receives at least one downscale image from the downscaling unit and accumulates the at least one downscale image, an afterimage detection unit that detects an afterimage from an accumulated downscale image obtained by the image accumulation unit and generates afterimage information, and a weight applying unit that receives the afterimage information, calculates a downscaling weight of a region of interest including the afterimage in the input image based on a time parameter, and provides the downscaling weight to the downscaling unit.