A method for simulating dark-part exposure compensation of high dynamic range images using a single image includes steps of: performing bright-part-enhancing image processing and saturation-contrast-enhancing image processing to obtain images P1, P2, respectively; selecting one of the images P1, P2; performing bright and dark parts identifying image processing on a selected image; performing blurring image processing on the selected image, to obtain a weight-reference image P3; and performing mixed weight calculation on pixels of the image P1 and pixels of the image P2 according to weights of pixels of the weight-reference image P3, respectively, so as to mix the image P1 and the image P2 to obtain a mixed image P4, wherein the pixels of the images P1, P2 on which the mixed weight calculation is performed correspond to the pixels of the weight-reference image P3, respectively. Hence, excessively dark parts typical of an image of undesirably high contrast are improved by reference to a single.