A stable and highly efficient Cu/TiO2 nanocomposite photocatalyst was successfully synthesized through atomic layer deposition (ALD). A series of spectroscopic tests confirmed that subnanoscale Cu particles were con formally dispersed on TiO2, and that TiO2 surface states could be modified by controllable Cu particles. The photodegradation of methylene blue and phenol under ultraviolet light was used as a probe for investigating the photocatalytic efficiency of the photocatalyst, and Cu-loaded TiO2 prepared through ALD was discovered to exhibit high and stable activity compared with that prepared through impregnation. These results prove that ALD is an effective strategy for improving the photocatalytic activity of TiO2, and that Cu/TiO2 is a photocatalyst that can effectively remove organic pollutants.