Vacuum ultraviolet (VUV) excitation and photoluminescent (PL) properties of Eu 3+ and Tb 3+ ion-doped aluminate phosphors, GdCaAl 3 O 7 :Eu 3+ and GdCaAl 3 O 7 :Tb 3+ have been investigated. X-ray diffraction (XRD) patterns indicate that the phosphor GdCaAl 3 O 7 forms without impurity phase at 900°C. Field emission scanning electron microscopy (FE-SEM) images show that the particle size of the phosphor is less than 3μm. Upon excitation with VUV irradiation, the phosphors show a strong emission at around 619nm corresponding to the forced electric dipole 5 D 0 → 7 F 2 transition of Eu 3+ , and at around 545nm corresponding to the 5 D 4 → 7 F 5 transition of Tb 3+ . The results reveal that both GdCaAl 3 O 7 :RE 3+ (RE=Eu, Tb) are potential candidates as red and green phosphors, respectively, for use in plasma display panel (PDP).