Abstract: A TiO₂ catalyst doped by Pb²⁺ was prepared by the sol-gel method and characterized by DRS and FS. The experimental results showed that Pb²⁺ strengthened the TiO₂ fluorescence apex, the absorbance band edge moved in the red direction, and the absorbance strengthened obviously both in the UV range and in the visible range. Compared with Ag-TiO₂, Bi-TiO₂ and TiO₂ films, the Pb²⁺-doped TiO₂ thin film has the highest photocatalytic activity by studying the degradation of methyl orange under UV-ray, which is an effective way to increase the photocatalytic activity.