We report the successful preparation of flower-like ZnO microstructures in one step by a simple, rapid and reliable ultrasound irradiation route, using only Zn(CH 3 COO) 2 and NaOH as starting materials. The product was characterized by powder X-ray diffraction, energy-dispersive X-ray spectrometry, transmission electron microscopy and scanning electron microscopy. The UV–vis absorption and emission spectra, photocatalytic activity and electrochemical properties of the as-obtained flower-like ZnO microstructures were studied.