This paper reports on the comparative investigation of the spectroscopic properties of the Y3Al5O12 (TAG) and Y3Ga5O12 (YGG) doped with Eu3+ synthesized by the combustion method. A pure phase was identified for the YGG phosphor, but one other phase was observed for the as-prepared and annealed TAG phosphor. A high intense red color emission was observed from Eu3+ doped YAG compared to the orange-red color of Eu3+ in the YGG phosphor. The optimum Eu3+ concentration was found to be higher in the YGG compared to the optimum Eu3+ concentration in the TAG. A spectroscopic investigation on the concentration quenching effect and the covalency of the Eu-O bond were carried out on the basis of the substitution of Ga3+ and Al(3+)in the garnet host. Judd-Ofelt parameters, different spectral and colorimetric parameters were estimated theoretically from the experimental curves, for both the hosts to determine the better luminescence media. (C) 2015 Elsevier B.V. All rights reserved.