ZnSnO3 one-dimensional (1D) strutures were synthesized by using an evaporation technique. The morphology, crystal structure, and enhanced sensing properties of the ZnSnO3 structures functionalized with Pd to CO gas at 300 degrees C were investigated. The diameters of the 1D structures ranged from a few hundreds to a few thousands of nanometers and that the lengths were up to a few hundreds of micrometers. The gas sensors fabricated from multiple networked ZnSnO3 rods functionalized with Pd showed the enhanced electrical responses to CO gas. The responses of the rods were improved 10.7, 13.7, 13.4, and 12.5 fold at the CO concentrations of 10, 25, 50, and 100 ppm, respectively. In addition, the mechanism for the enhancement in the gas sensing properties of ZnSnO3 rods by Pd functionalization is discussed.