A kind of optical data storage medium based on electron-trapping materials, Y3Al5O12:Ce3+ fluorescent ceramic, was developed by vacuum sintering technology. The medium shows sufficiently deep traps (1.67 and 0.77 eV). The properties of trap levels were researched by thermoluminescence curves, and the optical storage mechanism based on Ce3+ ion doping was proposed. More importantly, the data can be written-in by 254 nm UV light, and readout by heating (300°C). This work expands the application fields of fluorescent ceramics, and it is expected to promote the development of electron-trapping materials.