Hollow ZnSnO₃ nanocubes with peculiar cage- and skeleton-like architectures are successfully synthesized by a simple hydrothermal process at 180 °C for 12 h. These ZnSnO₃ nanostructures exhibit almost uniform cubic structures with side length of 200–400 nm. The gas sensor based on these ZnSnO₃ nanostructures exhibits high response and quick response-recovery to ethanol and HCHO, which also shows superior sensitive performance compared with the results of sensor based on solid ZnSnO₃ nanocubes.