We investigated the emission properties of Ce3+-doped BaSO4 (BaSO4:Ce) nanoparticles synthesized using the co-precipitation method. Rietveld refinement analysis of the X-ray diffraction patterns revealed that BaSO4:Ce was synthesized successfully without any impurities. Upon photo-excitation at λex = 247 and 267 nm, BaSO4:Ce showed two intense emission peaks at 300 and 320 nm, which were assigned to the 5d → 2F5/2 and 2F7/2 transitions of Ce3+ ions. Interestingly, we achieved modulation of the photoluminescence intensity by controlling the irradiation wavelength and irradiation time. In addition, optically stimulated luminescence and thermoluminescence characteristics were observed in the low-Ce3+ doping concentration region. These novel luminescent properties were attributed to defect states originating from the doping of Ce3+. Our results suggest that BaSO4:Ce nanoparticles prepared via the co-precipitation method have good properties for use in dosimeters as well as UV phosphors.