Titania nanowire arrays were synthesized in highly ordered porous anodic alumina template by sol-gel method. The samples were characterized by means of SEM, XRD. The photocatalytic property of TiO2, SiO2/ TiO2, F-/SiO2/TiO2 nanowire arrays were studied by methyl orange degradation. The results show that F-/ SiO2/ TiO2 nanowire arrays have higher photocatalytic activities than those of TiO2 and SiO2 /TiO2. Under the condition of 1 h irradiation, the degradation ratio of methyl orange exceeds 90%. At the same time, the higher photocatalytic activity and the smaller crystal size of F-/ SiO2/ TiO2 are related to the incorporation of F-.