The paper reported the fluorometric characteristics of sweet potato extraction solution for the determination of Zn2+ ion.The maximum wavelength of excitation and emission of the extraction solution are 369nm and 440nm respectively.The fluorescence of sweet-Lpotato extraction solution is quenched while Zn2+ ion solution is added.The fluorescence intensity(ΔF) exhibits linear with concentration of Zn2+ solution in the range of 2×10-6 to 2×10-2mol·L-1.The present method for the determination of Zn2+ is green,sensitive,and easy.