This study evaluates the photocatalytic activity of nickel oxide films synthesized by magnetron sputtering before and after thermal annealing. The effect of NiO film activation with gold nanoparticles is also investigated. Sample characterization performed by complementary techniques reveals formation of nanocrystalline cubic NiO and gold nanoparticles embedded into the NiO matrix. The ability of samples to decompose glycerol under ultraviolet (UV) and visible (VIS) light irradiation was tested. NiO films behave as active compound under UV light. Incorporation of gold nanoparticles into the oxide matrix not only enhances its activity under UV, but allows to decompose the model pollutant on the surface under the VIS light irradiation.