NOVELTY - A nanometer modified polymer fluorescent material comprises metal sulfide and modified hydrosulfuryl methylated polystyrene. The metal sulfide is nanometer cadmium sulfide, nanometer copper sulfide, nanometer zinc sulfide, or nanometer manganous sulfide.    USE - The nanometer modified polymer fluorescent material is used in ion detection and photovoltaic energy conversion.    ADVANTAGE - The material has multi-terminal group modification, controllable nanometer particle content, and strong macromolecule fluorescence.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing the nanometer modified polymer fluorescent material comprising:    (A) adding 4-vinybenzyl chloride and styrene in reaction container at mol ratio of 1:10-40;    (B) adding dibenzoyl peroxide evocating agent, where mol ratio of evocating agent and styrene is 1:100-150;    (C) polymerizing under protection of helium gas at 75-95 degrees C to obtain chloromethylated polystyrene;    (D) mixing chloromethylated polystyrene and thiourea at mol ratio of 1:1.2-1.5 in N,N-dimethylformamide as solvent;    (E) reacting under protection of helium gas at 100-110 degrees C in oil bath;    (F) adding sodium hydroxide solution (2-3 mol/L); reacting at 110-120 degrees C, and neutralizing with concentrated sulfuric acid;    (G) precipitating using methanol and then drying to obtain hydrosulfuryl methylated polystyrene;    (H) mixing hydrosulfuryl methylated polystyrene and metal sulfide at mol ratio of 5:1-20:1 in dimethyl formamide;    (I) stirring for 4-6 hours at room temperature, precipitating with methanol and then washing with water; and    (J) removing adhered inorganic material to obtain nanometer modified polymer fluorescent material, where vol. ratio of sodium hydroxide solution and the reacted material solution is 1:100.    DESCRIPTION OF DRAWING(S) - The drawing is a flow diagram illustrating a method for preparing nanometer modified polymer fluorescent material. (Drawing includes non-English language text).