A temperature window of single-walled carbon nanotubes(SWCNTs)growth has been studied by Raman spectroscopy.The results presented when temperature lowcr than 750℃,there were few SWCNTs formed,and when temperature higher than 900℃,mass amorphous carbons were formed in the SWCNTs bundles due to the serf-decomposition of CH4.The temperature window of SWCNTs efficiently growth is between 800 and 900℃,and the optimum growth temperature is about 850℃.These results were supported by transmission electron microscope images of samples formed under different temperature.The temperature window is important for large-scale production of SWCNTs by catalytic chemical vapor deposition method.