It is of great interest to develop gas-sensing materials with excellent performance in a facile and mild route. In this work, dandelion-like hollow ZnO hierarchitectures assembled with ZnO nanoparticles have been synthesized by annealing a zinc complex precursor, which was produced from zinc acetate and ammonium bicarbonate at room temperature. The nanoparticle size in the hierarchitectures enlarges from 10 to 23 nm with the annealing temperature increasing from 350 to 550 degrees C. The ZnO hierarchitectures have shown high sensing response (34.5), fast response (6 s) and recovery (7 s), and low optimal operating temperature (250 degrees C) toward 50 ppm ethanol because of large surface area and rich pore. Also, the obtained ZnO dandelion-like hierarchitectures exhibits good selectivity toward alcohols. The obtained results suggest that the dandelion-like ZnO hierarchitectures synthesized herein are a promising gas sensing material.