An image processing method, an image processing circuit and a display apparatus are provided. The image processing method includes: converting an RGB gray-scale value of each pixel in a current image frame into an RGB luminance value; converting the RGB luminance value into a first RGBW luminance value; determining a luminance level of the current image frame according to the first RGBW luminance value corresponding to each pixel; determining a luminance gain value of the current image frame according to the luminance level of the current image frame; calculating a second RGBW luminance value according to the luminance gain value and the first RGBW luminance value; and converting the second RGBW luminance value into an RGBW gray-scale value.