Abstract: A color-based sorting apparatus comprising, a material supplying device provided so as to discharge and supply the grains stored therein, a color detecting device detecting a color of each of the grains passing through a setting region, a sorting processing section operating to change a transference path for defective grains, a control device, which determines whether each of the grains to be sorted is defective or not based on a detection signal from the color detecting device, and when it is determined that one of the grains is defective, the control device activating the sorting processing section, and a feeding roll disposed between the material supplying device and the color detecting device and rotating around an axial line thereof to cause the grains to be sorted, which are supplied from said material supplying device aligned in an axial direction, to freely fall down toward the color detecting device.