An all-thin-film glass/ITO/MoO3/LiAlO2/NiOx/ITO device was deposited by magnetron sputtering for electrochromic application. The amorphous MoO3 and LiAlO2 thin films were prepared with the substrate temperature below 0 °C and in O2 and Ar gas pressure. The structure and surface morphology of the films were characterized by x-ray diffraction (XRD) and atomic force microscopy (AFM). It has been found that the amorphous LiAlO2 thin film was a suitable ion conductor for the electrochromic device. The transmittance in the wavelength range of 400-800 nm for the ITO/MoO3/LiAlO2/NiOx/ITO device changed from 14.48 % to 57.68 % by the applied voltage of 7 V. The blue-colored electrochromic property could be observed for the all-thin-film device. The experimental results indicated that such a monolithic system had great potential to be applied in flat-panel displays and smart windows.