A weighted image enhancement method includes receiving an original image. The original image includes several original pixels. The original image is sharpened to generate a sharpened image. The sharpened image includes several sharpened pixels. Edge detection is performed with respect to the original image to generate a probability of whether each original pixel is on an edge. An enhancement mode setting is received. A corresponding weight table corresponding to the enhancement mode setting is looked up to obtain a corresponding enhancement weight of each original pixel according to the probability of whether each original pixel is on an edge. A weight calculation is performed utilizing each original pixel and its corresponding sharpened pixel according to its corresponding enhancement weight to generate an enhanced image. The enhanced image is displayed by a display unit.