The invention discloses a color capture method and device based on a RGB color disk, and belongs to the technical field of color processing. The method comprises the steps of calculating a RGB value of a color point according to the coordinate of the color point in the color disk; converting the RGB value to a brightness value, a chromatic value and a saturation value; sending the brightness value, the chromatic value and the saturation value to a color display device. According to the method and device, when the characteristic that distribution of three primary colors, namely red, blue and green, is in accordance with certain regularity is utilized, a color is captured through the coordinate in the RGB color disk, and then all colors in the RGB color disk can be captured without edge errors.