A variety of ZnO belt-like structures were synthesized by the heat treatment of ZnS substrates with Ga droplets in the air, and their morphological and structural properties were investigated. Three types of ZnO belts with flat surfaces of (20), (100) and (23) were obtained. As comparison, the ZnO crystal growth was examined by the thermal oxidation of ZnS only. These results highlight the promise of the heat treatment with Ga in the synthesis of oxide nanostructures.