Atmospheric pressure plasma jet has received increasing attention due to its wide potential applications such as in material processing and surface modification. This paper presents the characteristics of titanium oxide (TiO ₂) thin films deposited by using atmospheric pressure corona plasma jet based on a needle-plate configuration. The influences of corona polarity and operating parameters on the properties of TiO ₂films are investigated. The characteristics of positive and negative corona discharge, the developing process and the emission spectrum of the plasma jet are tested, and the TiO ₂films prepared under different conditions are measured and analyzed. The results show that the TiO ₂film prepared by negative corona plasma has a more uniform surface, and the Ti content in TiO ₂film is higher than that by the positive corona plasma. The adhesion force is higher than 4.7 N/cm and the surface resistance of the film is less than 10 ¹⁰Ω. The deposition of the TiO ₂film is closely related to the nucleation mechanism of the precursor in the plasma jet and/or the interface between jet and substrate. These results will provide useful reference for preparing uniform and functional oxide film materials by atmospheric pressure plasma jet.