0.5% Ce³⁺ doped BaCa₂MgSi₂O₈ phosphor was prepared by a conventional solid state reaction method. Luminescence spectra as well as fluorescence decay were monitored in the VUV-UV range. Ce³⁺ emissions are assigned to cerium ions on a Ba²⁺ site, and the five 4f–5d excitation bands of Ce³⁺ were determined at low temperature. The light yield is estimated to be around 10 600 ph MeV⁻¹ under X-ray excitation. X-ray absorption near-edge structure (XANES) was explored to study the energy transfer efficiency to optical centers from each element in the phosphor; the results show that the contributions to luminescence are not identical for each element.