A method of manufacturing, with high purity and high efficiency, a multi-wall carbon nanotube (10) having layers densely fitted to the center part thereof, comprising the step of leading a graphite rod (2) into plasma flame (1) generated in the atmosphere of inert gas (4) added with hydrogen to evaporate carbon so as to stack the densest multi-wall carbon nanotube (10) on the surface of the graphite rod (2).