Li1.3Al0.3Ti1.7(PO4)3 thin films were successfully prepared by the solution deposition using lithium acetate, aluminum nitrate, ammonium dihydrogen phosphate and titanium butoxide as starting materials. The structure, surface morphology, electrochemical window, and ionic conductivity of the films were studied by X-ray diffraction, scanning electron microscopy, cyclic voltammetry and AC impedance. The results showed that Li1.3Al0.3Ti1.7(PO4)3 thin films annealed between 750 ℃ and 900 ℃ prepared by this method were well crystallized, homogenous and crack-free. The electrochemical window was beyond 2.4 V and the ionic conductivity was approximately 1.57×10(-5) S/cm at room temperature for the film annealed at 800 ℃ for 30 min.