Blue-emitting phosphor of Ce3+-activated fluorosilicate apatite Ba2Y3[SiO4]3F was prepared via conventional solid-state reaction method. The X-ray powder diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL) excitation and emission spectra, and the decay curves (lifetimes) were applied to characterize the phosphors. The effects of Ce3+ activator concentration on the luminescence properties were investigated. Ba2Y2.85Ce0.15[SiO4]3F exhibits the brightest blue emission with CIE coordinates of (x = 0.231, y = 0.301). The crystallographic site of Ce3+ ions in Ba2Y3[SiO4]3F lattices was identified. Two kinds of crystallographic Ce3+ occupying MI and MII sites in Ba2Y3[SiO4]3F lattices result in two distinct emission centers. The internal PL quantum efficiency, the temperature-dependent luminescence, and the activation energy of thermal quenching were investigated to evaluate the potential application. This is a new kind of blue-emitting phosphor based on apatite structure.