A copolymer based on 1,4-di(thiophen-3yl)benzene and pyrene was electrochemically synthesized and characterized. The copolymer film showed a stable and well-defined redox process. Furthermore, five various colors under different potentials were presented on the copolymer film. Besides, the copolymer film showed fast switching time (1.5 s at 750 nm, 1.0 s at 1100 nm). Cyclic voltammetry study reveals that the copolymer film has reasonable stability.