Abstract: This research was on surface color discrimination of achromatic color in congenital red-green color- vision abnormal people. The results showed that The △E of congenital red-green abnormal people varied with the changes of the grade of visual evaluation, there were certain differences in surface color discrimination of achromatic color between congenital red-green abnormal people and normal people; the changes of upper limit and lower limit of the same brightness grade had effect on surface color discrimination of congenital red-green abnormal people, the effect was concerned with brightness grades.

Key words: Congenital red- green color-vison abnormal people, surface color discrimination, color difference