To improve the photocatalytic activities of TiO₂, SnO₂@TiO₂ core-shell structure was synthesized. SnO₂ nanowires were prepared by chemical vapor deposition (CVD) based on the VLS growth mechanism, and then TiO₂ was deposited on the surface of SnO₂ nanowires by Atomic Layer Deposition (ALD) using tetraisopropyltitanate as the metal precursor. The results showed that titanium dioxide possesses the rutile structure in SnO₂@TiO₂ core-shell structure and the anatase structure appears by the effect of the intercalation of Al₂O₃. To examine the photocatalytic activity for degradation of methyl orange solution under ultraviolet light, the thickness and crystal structureof TiO₂ in the core-shell structure were studied