TiO2 coatings were prepared on TC4 titanium alloy substrate via magnetron sputtering technology with TiO2 ceramic and Ti metal targets, respectively. The coatings were characterized using scanning electron microscopy, X-ray diffractometer, X-ray photoelectron spectrometer, scratch tester, and electrochemical workstation. The microstructure, bonding strength, hydrophilicity, and corrosion resistance of the coatings were systematically investigated. The results showed that both coatings had an amorphous columnar structure with comparable hydrophilic properties, and the Ti element existed as TiO2. TiO2 coatings synthesized from ceramic targets demonstrated significantly improved density, bonding strength, and corrosion resistance compared to those prepared from metal targets.