The xNb2O5-(15-x)La2O3-40B2O3-45BaO (x=5, 7.5, 12.5 mol%) glasses doped with Eu3+ ions in 1 mol% are fabricated by the melting method. The Fourier transform infrared (FTIR) spectra, phonon side-band spectra, emission and excitation spectra of the glasses are measured. The crystal field parameter and