In this work, a columinescence system is found for lanthanide complexes Ln(p-ABA)3⋅H2O (p-ABA: p-aminobenzoic acid) incorporated in silica matrix. It is found that the luminescence quantum yield of Tb3+ emissions increases remarkably when partly replacing Tb(p-ABA)3⋅H2O by Gd(p-ABA)3⋅H2O in silica glass. Moreover, through the ratio of the fast to the slow heat components derived from a photoacoustic method, the intrinsic luminescence quantum yield of Tb3+ and the ligand sensitization efficiency are determined for the samples. The luminescence quenching effect for Tb–Er(p-ABA)3⋅H2O complexes in silica matrix is also discussed.