As the novel Eu-doped MgIn2-xGaxO4 (x = 0-0.3) phosphors were synthesized by solid-state method, their characterization and luminescent properties were also investigated. X-ray dirraction results revealed that the Eu3+ ions are well dissolved into the MgIn2-xGaxO4 host below x = 0.2. The Eu3+ ions preferred to occupy the distorted octahedral sites in the MgIn2-xGaxO4 structure making the electric-dipole transition prominent. The extraordinary excitation spectrum showed only intense f-f transition of Eu3+ ions around 467 nm without a charge transfer band. Under excitation, the as-obtained powders emitted bright red light at 615 nm (D-5(0 ->) F-7(2)). The intensity ratio of D-5(0) -> F-7(2) to D-5(0) -> F-7(1) increased with Ga concentration and reached the maximum of x = 0.2. Thus, the MgIn1.8Ga0.2O4: 5 atom % Eu3+ phosphor has good luminescent performance. (c) 2005 The Electrochemical Society.