We have synthesized high‐quality, nanoscale ultrathin ZnO films at relatively low temperature using a facile and effective hydrothermal approach. ZnO films were characterized by scanning electron microscope (SEM), X‐ray diffraction (XRD), Raman spectroscopy, photoluminescence spectra (PL), and UV‐vis absorption spectroscopy. The products demonstrated 95% photodegradation efficiency with Congo red (CR) after 40 min irradiation. The photocatalytic degradation experiments of methyl orange (MO) and eosin red also were carried out. The results indicate that the as‐obtained ZnO films might be promising candidates as the excellent photocatalysts for elimination of waste water.