Oxygen vacancy defects and Fe 2+ impurity defects were produced in PbWO 4 crystal growth process due to oxygen deficient, which lead to the coloration of the crystal and the optical properties lower. Doped Sb 2O 3 into the crystal, the oxygen vacancy had been dispeled, and Fe 2+ had been oxidized to Fe 3+ which is colourless. The optical properties and the scintillation characteristics has been enhanced.