<p>The ZnWO₄–ZnO composite thin film ceramic humidity sensors were fabricated by direct current magnetron sputtering method. X-ray diffraction and energy dispersive spectroscopy spectra confirm at sputtering powers of 20 W and 30 W, both ZnWO₄ monoclinic phase and ZnO hexagonal phase are present in the films, forming the ZnWO₄–ZnO composite films. When the sputtering power is 40 W, the film is composed of a single ZnWO₄ phase. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) images show that as the sputtering power increases, the grain size gradually increases, the grain boundary area decreases, and the surface roughness of the film reduces. Compared with the pure ZnWO₄ film, the ZnWO₄–ZnO composite film shows enhanced humidity performance, improved sensitivity, and reduced response time and recovery time by half. It is because the band gap of ZnO is smaller than that of ZnWO₄, making it easier to interact with water molecules, which results in higher sensitivity and faster response of the film. In addition, the ZnWO₄–ZnO composite films have larger roughness and more grain boundary area, which can provide more active sites for the adsorption of water molecules, thereby improving the humidity performance.</p>