An auto-color-correction method for an image capturing device includes calculating a plurality color temperatures of a plurality of pixels in an image; calculating a number of pixels of the plurality of pixels located in a first color temperature range as a first number and a number of pixels of the plurality of pixels located in a second color temperature range as a second number; generating a color temperature weight according to the first number and the second number; and generating at least one correction coefficient according to the color temperature weight, at least one first coefficient corresponding to the first color temperature range and at least one second coefficient corresponding to the second color temperature range.