To achieve a high efficiency of the thermoacoustic engine with a looped tube, we have to suppress an acoustic streaming such as Gedeon streaming. A lubber membrane and 'Jet Pump' can work as an acoustic-streaming suppressor. In this study, we use a lubber membrane as an acoustic-streaming suppressor, and determine the affect of position of the membrane to the onset temperature ratio and the acoustic field formed in the looped tube thermoacoustic engine. As a result, the optimum position of the acoustic-streaming suppressor to decrease the onset temperature and to generate traveling wave mode was determined.