The photophysical properties of a complex based on diphenylphosphanoethane (DPPE) fluorescent ligands linked to a europium ion have been investigated by different spectroscopic methods. Upon complexation with europium, the interaction of the phosphane oxide group with europium leads to a red shift of the absorption spectrum and a strong quenching of the ligand emission. The typical sensitized emission of Eu3+ is observed upon excitation of the ligand with a fluorescence quantum yield of 1%. Time-resolved absorption and emission experiments have been performed in order to investigate the photophysical mechanism involved in this complex. Photophysical studies show that an energy-transfer mechanism occurs from both the first excited singlet and triplet states of the ligand, and the population of the europium ion to the D-5(1) state takes place, from which the D-5(0) state is populated. Additionally, electron transfer from the excited singlet state of the ligand to the europium ion appears as a very efficient process