This paper briefly introduces the formation and fluorescence emission of excimer of pyrene chromophore based on its steady-state fluorescent spectra. The method and pattern for chemically labeled pyrene groups onto polymer chains are also illustrated. We discuss the excimer formation of pyrene labeled on water-soluble polymers and review applications of the excimer spectra on studying hydrophobic interaction

electrostatic interaction

hydrogen bonding

complex and so on. This excimer fluorescence of pyrene labels is also used in research of the volume phase transition of polymer gels and the molecular chain dynamics.