Tricolor emission Ca2SiO4:Ln (Ln = Ce3+, Eu2+, Sm3+) phosphors were synthesized by the conventional solid-state reaction method, and their photoluminescence properties were investigated. Ce3+-, Eu2+-, or Sm3+-doped Ca2SiO4 phosphors showed typical blue, green, or red luminescence in the CIE1931 chromaticity diagram, respectively. In addition, the luminescence efficiency of the tricolor emission Ca2SiO4:Ln (Ln = Ce3+, Eu2+, Sm3+) phosphors was evaluated. A series of white light-emitting diode (LED) prototypes were fabricated by combining near-UV LED chip and the as-prepared tricolor emission phosphors with various ratios in weight. White LED prototypes with tunable correlated color temperature and color-rendering index values were realized by controlling the amount of phosphors. The presented results indicated the potential application of Ca2SiO4:Ln (Ln = Ce3+, Eu2+, Sm3+) phosphors in near-UV white LED.