The electrochromic effect, change of optical transmittance with respect to the applied DC voltage,is a well-known phenomenon. The electrochromic film can be fabricated with various methods such as rf and dc sputtering, chemical vapour deposition, electron, thermal and ion cluster beams and several other methods. Sol-gel process offeres several advantages over conventional deposition method for the control of stoichiometry and film structure. It was known that WO3 thin film doped with niobium and with Lithium exhibits a well bleaching process as compared with pure tungsten oxide film [1-4]. The presence of Li, Ta, Ti and Nb in WO3 film improves the spectroelectrochemical response of these materials. So in this paper, we presented a mixed-metal oxide sol-gel synthesis, deposition, optical and electrochromic performances of Nickel (II) acetate doped tungsten molybdenum oxide film WO3-MoO3--Ni(CH3COO)2. The range of dopant concentration was 0.75ml-7.5ml V%. Film made from WO3-MoO3 precursor solutions was also used for comparison. The film has been studied and characterized by ultraviolet-visible spectroscopy, X-ray diffractometry (XRD), scanning electron microscopy (SEM) and electrochemistric station. The good coloring and bleaching behaviors of doped Ni film mean that they are suitable for electrochromic material.