A new fluorescent switch based on a photochromic diarylethene, 1-[2-methyl-5-(4-hydroxymethylphenyl)-3-thienyl]-2-[2-methyl-5-(4-azidomethylphenyl)-3-thienyl] perfluorocyclopentene has been synthesized, And its properties have been discussed systematically in acetonitrile solution and in PMMA, such as photochromic, fluorescence switch and kinetics experiments, and its optoelectronic properties, The results showed that this compound exhibited reversible photochromism and the maxima absorption of compound closed-ring isomer 1c is 590 nm. Its fluorescence intensity decreased along with the photochromism from open-ring isomers to closed-ring isomers.