Recently, DME (dimethyl ether, CH3OCH3) has attracted a great deal of attention as an alternative fuel owing to its easy transportation and cleanliness. This study was conducted to verify the combustion performance and to identify potential problems when DME is fueled to a gas turbine. Combustion tests were conducted by comparing DME with methane.. which is a major component of natural gas, in terms of combustion instability, NOx and CO emissions, and the outlet temperature of the combustion chamber. The results of the performance tests show that DME combustion is very clean but hard to control. The CO emission level of DME is lower than that of methane, while the NOx emission level of DME is as low as that of methane. When firing DME, the pressure fluctuation in the combustion chamber caused by combustion instability is lower than that occasioned when firing methane. From the results of the outlet temperature of combustor we have ascertained that DME combustion is more likely to flash back than methane combustion and this property should be considered when operating a gas turbine and retrofitting a burner. (C) 2007 Elsevier Ltd. All rights reserved.