K0.5Bi4.5Ti4-x(Al0.5V0.5)(x)O-15 (KBT-AlV, x = 0.00, 0.04, 0.06 and 0.08) ceramics were prepared by using the conventional solid-state reaction method. Phase analysis was performed by X-ray diffraction, and micro-structural morphology was assessed by scanning electron microscopy. The Effect of aluminium and vanadium on the structures, morphologies and electric properties of the K0.5Bi4.5Ti4O12 (KBT) ceramics were investigated. Frequency dependence of the dielectric constant exhibited that the dielectric constant of the KBT ceramic is enhanced gradually by the aluminium and vanadium modification and a giant dielectric constant (5.4 x 10(4) at 100 Hz) can be observed in the KBT-AlV specimens. Moreover, the reasons for the giant dielectric constant of the KBT-AlV ceramics are discussed.