Supported bimetallic Pt-Sn catalysts with different carriers were prepared through a one-step reduction method for the gas phase hydrogenation of acetic acid to ethanol. The structure of the catalysts was characterized by X-ray diffraction, transmission electron microscopy and energy-dispersive X-ray spectroscopy. Among these catalysts, the carbon nanotube-supported bimetallic Pt-Sn catalyst (Pt-Sn/CNT) showed the best performance, exhibiting over 97% conversion and 92% selectivity to ethanol under relatively mild conditions. The addition of Sn to Pt catalyst inhibited the C-C bond cleavage activity and enhanced the selectivity of the catalyst to ethanol, due to the formation and well-dispersion of PtSn alloy on the CNT surfaces. The catalytic performance depended on the ratio of Sn and Pt and the particle size of PtSn alloy. The one-step reduction method was conductive to preparing catalyst with smaller PtSn alloy particles and higher performance, which was shown that the optimized Pt-Sn/CNT with average PtSn alloy particle size at 3.0 nm can retain its high catalytic performance for over 300 h on stream. (C) 2013 Elsevier B.V. All rights reserved.