In this work,a newly synthesized ligand,trisalicylicamido triethylamine,acts as a specific reagent for enhancing the fluorescence intensity of Eu Ⅲ complex with thenoyltrifluoroacetone.The spectrofluorimetric determination of trace amounts of Eu III based on the above system was carried out and its luminescence mechanism was studied.The excitation and emission wavelengths are 348.9 nm and 613.4 nm, respectively. The fluorescence intensities vary linearly with the concentration of EuIII in the range 7.598 ×10-7g l-1-3.799 ×10-4g l-1 with a detection limit of 1.520×10-8g l-1 and a standard deviation of 1.80 × 10-6g l-1 for 10 measurements.The interferences of some rare-earth metals and inorganic ions are described.This method is a direct,rapid,selective and sensitive analytical procedure for the determination of trivalent europium in high purity yttrium oxide.