SnO2 decorated graphene oxide (GO) composites were fabricated via electrophoretic deposition (EPD). The ratio of GO to SnO2 in the composites was controlled from 1:0 to 1:6. The catalytic effect of added SnO2 was explored on gas sensing behaviors of the intercalated or sandwich composite structure. Room temperature gas sensing was performed with the SnO2/GO composite sensors resulting from its high specific surface and interactions between SnO2 and GO. Moreover, the transition behavior between n-type and p-type gas sensing was observed when heat-treatment of the GO sensors was conducted. Gas selectivity of the sensors was investigated using three types of VOC gases (formaldehyde, toluene, and styrene). These composite sensors can be effectively employed for multiple gas detection. (c) 2017 The Electrochemical Society. All rights reserved.