Glycerol which is a byproduct of biodiesel production is considered as a potential feedstock for syngas production with the increase of biodiesel demand. In this study, the characteristics of glycerol gasification under a microwave plasma torch with varying oxygen and steam supply conditions were investigated. The experimental results demonstrated that the gasification efficiency and syngas heating value increased with the supplied microwave power while the increase of oxygen and steam led to a lower gasification performance. In order to achieve high carbon conversion and cold gas efficiency in the microwave plasma gasification of glycerol, the O-2/fuel ratio should be maintained at 0-0.4. It was revealed that the fuel droplet size and the mixing effect and retention time inside the plasma flames are critical factors that influence the product gas yield and gasification efficiency. This study verified that syngas with a high content of H-2 and CO could be effectively produced from glycerol through microwave plasma gasification. Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.