A gamma voltage conversion circuit includes: a first voltage divider circuit having first input terminals and first voltage divider output terminals, wherein each first input terminal is configured to receive a first gamma voltage signal, the first voltage divider circuit is configured to generate first analog voltage signals according to the first gamma voltage signal, and each first voltage divider output terminal is configured to output one of the first analog voltage signals; a Gray code control circuit configured to generate and output a Gray code control signal according to a grayscale value to be displayed; a first encoding circuit configured to generate and output second analog voltage signals according to the Gray code control signal and one of the plurality of first analog voltage signals; and a first output control circuit configured to generate and output an analog grayscale voltage signal according to the second analog voltage signals.