The growth of nickel oxide film grown on indium–tin oxide/glass substrate by liquid phase deposition is enhanced under ultraviolet photo-irradiation was studied. α-Ni(OH)2 dominates the composition of as-grown NiO film. After thermal treatment at 300 °C, α-Ni(OH)2 is transformed into NiO. For thermally treated NiO under ultraviolet photo-irradiation, the recrystallization and the colored and bleached transmittance after 50 times electrochromic test were improved. Both improvements come from fluorine passivation.