A conjugated copolymer, poly[2,7-di(2-furyl)fluorene], with periodic dielectric microstructure is prepared by electrochemical polymerization using cholesteric liquid crystal as an electrolyte solution. The polymer film thus prepared displays a labyrinthine fingerprint texture formed by a convexo-concave structure, and exhibits a random diffraction grating function. This anisotropic electrochemical polymerization technique is a novel bottom-up approach for preparing one-dimensional photonic crystals.