The WO3 films are prepared on the substrate of FTO conductive glass by using the ammonium metatungstate as the tungsten source and Pluronic F127 as the coordination polymer. The influence of the coordination polymer on the electrochromic performance of WO3 films is investigated. The experimental results show that the WO3 films have a cubic crystal structure. With the increase of the Pluronic F127 content, the WO3 film roughness increases, and the charge capacity increases first and then decreases. When the Pluronic F127 content is 26%, the charge capacity of the WO3 thin films is the largest, and the electrochromic performance is the best. The optical modulation range is up to 62.68% and the optical density difference is up to 0.864 in the visible region. Meanwhile, the total solar energy transmittance in the colored state is lower than that in the bleached state. The prepared thin films have a good energy saving effect.