Innovative electrochromogenic nanomaterials such as composite materials and also hybrid films can improve electrochromic performance, because of their potential application qualities in electronic, low-power screens, automotive anti-reflect mirrors, and smart windows. In this study, we used a hydrothermal method to used grow the CeO2 nanorods both with and without HCl added to the solution. And also, DC magnetron sputtering was used to deposit the tungsten oxide films on the cerium oxide nanorods. The surface plasmon effect changes with the size of CeO2 Nanorods, and this phenomenon influences electrochromic outcomes. The electrochromic characteristics of CeO2/WO3 nanostructures on FTO-coated glass are examined in the visible spectrum to use a 0.5 M concentration of H2SO4 as such electrolyte. At 600 nm, these structures produce significant optical modulation (50 %) and coloring efficiency (11.60 cm2/C at 700 nm).