In this paper, the photocatalytic activity enhancement of TiO2 thin films was realized by laser irradiation. The H2 yield of the as-irradiated film is 79 μmol/(h*m2), which is 33% more than that of the as-deposited TiO2 film. Spectrophotometer, X-ray diffraction and Raman system were employed to characterize the samples. The results showed that both the scanning rate and line spacing of the laser modification have effects on photocatalytic activity. It suggests that a phase junction is formed between the amorphous and rutile phases. The increment of H2 generation could be attributed to the alignment of Fermi levels in the phase junction.