A crown ether modified 5,15-meso，meso-porphyrin 1, as a model compound of a fluorescence switch, was designed and synthesized, and Cu+ ion was selected as quencher to investigate its switch effect. It was founded that the direction of excited electron transfer can be adjusted through changing the stimulation to different light-emitting components in the compound, and also display effective fluorescence switching property under the regulation of Cu+ ions. The target compound 1 was delibratively characterized and its switching properties were reasonablly explained.