The TiO2 nanocomposite doped by Si and Cu were prepared via sol–gel method under process control. The effects of doping and calcination temperature on the structural and photo-catalytic properties of applied nanocomposite have been studied by X-ray diffraction (XRD), scanning electron microscope, transmission electron microscope, FTIR and UV–vis absorption spectroscope. XRD results suggest that adding dopants has a great effect on the crystallinity and particle size of TiO2. Titania rutile phase formation was inhibited by Si4+ and promoted by Cu2+ addition doping. The activity of the photocatalyst was evaluated by photocatalytic degradation kinetics of aqueous methyl orange under visible radiation. The results show that the photocatalytic activity of the 20% Si doped TiO2 nanocomposite have a larger degradation efficiency than 5% Cu doped TiO2 under visible light.