2 inch size Ce0.2, 1%, 2.5% and 3% doped Gd3(Ga,Al) 5O12 (GAGG) single crystals were grown by the Cz method. Luminescence and scintillation properties were measured. Light yield change along the growth direction and effects of Ce concentration on scintillation properties in Ce:GAGG were studied. Ce3+ 5d-4f emission within 520-530nm was observed in the Ce:GAGG crystals. The Ce1%:GAGG sample with 5×5×5mm size showed the highest light yield of 62000 photon/MeV. The energy resolution was 4.7%@662keV. With increasing solidification fraction, the LY were decreased. It is proposed that the increase of Ga concentration along the growth direction is the main cause of the decrease of LY. The scintillation decay times were accelerated with increasing Ce concentration in the Ce:GAGG crystals. The scintillation decay times were 92.0ns, 79.1ns and 68.3ns in the Ce1, 2 and 3% GAGG, respectively. Ce0.2% sample showed scintillation decay time of 61.9ns (49%) with slower decay component of 595ns(51%).