A reflective display device using photonic crystals includes a plurality of reflective color filters, each reflective color filter reflects a predetermined wavelength range of an incident visible light; and a plurality of optical switches disposed adjacent to and facing a corresponding one of the plurality of reflective color filters, each of the plurality of optical switches extracts a predetermined color by adjusting an intensity or on/off-frequency of light reflected from the corresponding one of the plurality of reflective color filters. Accordingly, a reflective display device using photonic crystals may have a simplified structure requiring no conventional reflecting mirror.