The work aims to study the effects of different contents of Ni2+ on the hydrophilicity of TiO2 nono-coating. Different contents of metal ion Ni2+ doped TiO2 nanocomposite sols were prepared by sol-gel method, and different contents of Ni2+ doped TiO2 composite coatings were obtained by dip-coating method and heat treatment to form coating on the glass slide. The TiO2 doped with different concentration of Ni2+ was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet-visible spectrophotometer (UV-Vis), Fourier transform infrared spectrometer (FT-IR) and surface contact angle meter, and the crystal form, coating morphology, light absorption properties, structural composition and hydrophilicity were analyzed, and thereby the best composite coating formulation with appropriate content of metal ion Ni2+ was determined. The results showed that TiO2 consisted of anatase phase and a small amount of rutile phase, the doping of Ni inhibited the transition from anatase phase to rutile phase. The grain size gradually reduced with the increase of Ni content. The surface morphology of nano TiO2 coating with appropriate doping of Ni2+ was smooth and the particle distribution was dense and uniform. The doping could make the absorption wavelength threshold shift towards long wave and reduce the band gap, and effectively improve the hydrophilicity of TiO2 coating to a certain extent. When the mass fraction of Ni2+ was 1.5%, the hydrophilicity of TiO2 coating was the best. The modification of nickel ion doped TiO2 is achieved by sol-gel method. After doped into Ni2+, the hydrophilicity of Ni2+/TiO2 composite coating is significantly improved.