A titanium oxide showing sufficiently high photocatalytic activities by irradiation of visible light is provided. Using the titanium oxide, an excellent photocatalyst and photocatalyst coating composition are also provided. The titanium oxide has a selected ion chromatogram in which an evolution gas having 28 of a ratio of mass number to electric charge quantity exhibits at least one peak at about 600 C. or higher, the selected ion chromatogram being measured in a thermogravimetry-mass-spectroscopy.