3at.% Eu3+-doped La2-xGdxZr2O7 (x=0-2.0) transparent ceramics were fabricated by vacuum sintering. The effect of Gd content on crystal structure, in-line transmittance, and luminescence property of the ceramics were investigated. The ceramics are all cubic pyrochlore structure with high transparency. The cut-off edge of the transmittance curve of the ceramics varied with Gd content and was also affected by the annealing process. The luminescence intensity became stronger for the ceramics annealed in air. As Gd content increased, the energy band structure as well as the luminescence behavior of the ceramics was changed; in addition, the symmetry of the crystal lattice reduced, resulting in the shift of the strongest luminescence peak from 585nm to around 630nm.