A method of manufacturing a acute tip, multi-wall carbon nanotube radial aggregate, comprising the steps of leading a graphite rod into plasma flame generated in a hydrogen-added inert gas atmosphere to evaporate carbon from the graphite rod and stacking, on the surface of the graphite rod, the acute tip, multi-wall carbon nanotube radial aggregation of novel carbon nano-structure useful as field emission electron sources such as probes for STM and APM, display elements, and displays.