Yttrium aluminium garnet (YAG) single crystals and ceramics with different Ce3+-doping concentrations (mole fraction) are prepared. The luminous flux, photoelectric conversion efficiency, color rendering index, and color temperature of Ce∶YAG single crystals and ceramics under laser excitation are also analyzed. Under the excitation of the laser with a current of 2.6 A, the luminous flux of ceramics with a Ce3+-doping concentration of 0.3% is the highest at 617.2 lm. The single crystals with a Ce3+-doping concentration of 0.5% have a high color rendering index of 62 and a color temperature of 5841 K. Under the excitation of the laser with a power of 2.61 W and a power density of 10.8 W·mm-2 at the material center, the optical conversions of Ce∶YAG single crystals and ceramics are both unsaturated and the corresponding optical-to-optical conversion efficiencies are both about 240 lm·W-1. The experimental results show that the ceramics and single crystals are suited to produce high brightness white light under high power density laser excitation.