Disclosed are compositions and synthetic methods of phosphors that can be efficiently excited by blue light. The wavelength of the blue light is between 400 nm to 480 nm. The phosphors contain garnet fluorescent material activated with cerium, which contain Ba, Y, Tb, Lu, Sc, La, Gd, Sm, or combinations thereof, and Al, Ga, In, or combinations thereof. In addition, the phosphors are easily and quickly prepared in a large amount. The phosphors have high thermal stability and high emission intensity, therefore, being high of value in industry for utilization.