Single-phase Ca3Sc2Si3O12:Ce3+ green emission phosphor was synthesized by the hydrothermal silicon alkoxide gelation method. Such specimens demonstrated higher emission intensity than the Ca3Sc2Si3O12:Ce3+ samples that are prepared by conventional solid-state reaction method. It was also demonstrated that annealing in the presence of graphite as an oxygen scavenger significantly improves the fluorescence properties of this material.