•Transmittance of the Ce:LuAG ceramic (2mm thickness) reaches ~80% at 550 nm.•No secondary phases and micro-pores observed at grain boundaries and inner grains.•Ce:LuAG show a high steady state scintillation efficiency under X-ray excitation.•Air-annealing process could improve the LY of Ce:LuAG ceramic significantly.•Radiation induced absorption of Ce:LuAG ceramic was away from its emission band.Ce3+:Lu3Al5O12 (Ce:LuAG) scintillator ceramics were fabricated using solid state reaction method. High transparency (∼80% at 550 nm) was obtained, the grain boundary was clean and no secondary phase was observed. After further optimized by an air-annealing process, Ce:LuAG ceramic shows a much higher steady state scintillation efficiency than that of BGO single crystal under X-ray excitation, and the light yield (137Cs, 662KeV) improved around double compared with that of the before one. The radiation hardness of Ce:LuAG ceramic was investigated under 60Co gamma radiation with dose of 2 × 105 Gy and a dose rate of about 1 × 104 Gy/h. The radiation induced absorption appears in ∼380 nm and 610 nm (away from the emission band of Ce:LuAG) demonstrating its perspective for application in High Energy Physics.