An image display processing method for a display device, an image display processing device, a display device, and a non-volatile storage medium are provided. The display device includes a backlight unit, and the backlight unit is divided into a plurality of display backlight blocks and driven by a local dimming mode. The image display processing method includes: determining at least one boundary backlight block corresponding to a display image in the plurality of display backlight blocks; determining at least one target pixel and at least one background pixel corresponding to each boundary backlight block, and obtaining a backlight value of each boundary backlight block based on a grayscale value of the at least one target pixel and a grayscale value of the at least one background pixel; and displaying the display image.