A precursor of the Y3Al5O12:Ce (YAG:Ce) phosphor was obtained by co-precipitation of the solution of high purity nitrates with ammonium bicarbonate solution. The precipitation process of the precursor was studied in this work. YAG:Ce yellow phosphors with fine morphology was synthesized by annealing the precursor at a reducing atmosphere. The crystal phase, microstructure of the phosphors and their photoluminescence were investigated. The results indicated that the pure phase of YAG:Ce could be obtained at 1673 K annealing temperature. The particles of phosphor were basically spherical in shape with the mean size less than 2 μm. The excitation spectrum showed a broad and strong absorption band at about 460 nm, compatible with the excited wavelength of commercial blue light emitting diode (LED) for white LED lighting. Bright yellow-emission located at 540 nm was observed. A precursor of the Y3Al5O12: Ce (YAG: Ce) phosphor was obtained by co-precipitation of the solution of high purity nitrates with ammonium bicarbonate solution. The precipitation process of the precursor was studied in this work. YAG: Ce yellow phosphors with fine morphology was synthesized by annealing the precursor at a reducing atmosphere. The crystal phase, microstructure of the phosphors and their photoluminescence were investigated. The results indicated that the pure phase of YAG: Ce could be obtained at 1673 K annealing temperature. The particles of phosphor were basically spherical in shape with the mean size less than 2 μm. The excitation spectrum showed a broad and strong absorption band at about 460 nm, compatible with the excited wavelength of commercial blue light emitting diode (LED) for white LED lighting. Bright yellow -emission located at 540 nm was observed.