In the novel europium(Ⅲ) complex of the form ［Eu(tta)4·DEASPI］, the sensitization of lanthanide luminescence is via functional cation. The photophysical sensitization process of Eu(tta)4·DEASPI involves an energy transfer from charge transfer excited state of hemicyanine (aminostyrylpyridinium) cation, and the sensitization mechanism follows Frster resonance energy mechanism. The solvent effect on this new kind of europium(Ⅲ) complex was investigated in the present work. The europium(Ⅲ) complex was dissolved in a variety of solvents, i.e. acetone, DMF, ethanol and acetonitrile, and the emission intensity of europium(Ⅲ) complex in acetonitrile is much higher than in other solvents. The detailed discussion about solvent effect is provided in this paper.