A polymer system based on polydiacetylene (PDA) supramolecules that emits red, green, and blue fluorescence has been constructed. The three-color emitting system is comprised of red-fluorescent PDA vesicles in which green-fluorescent fluorescein molecules are encapsulated. Finally, the blue-fluorescence component is introduced by reacting terminal amine groups on the PDA vesicle surfaces with fluorescamine. Thin PDA-polymer-containing poly(vinyl alcohol) films formed by using this strategy display red, green, and blue fluorescence upon excitation with light at specific wavelengths.