A method of realizing selective separation of metallic single-walled carbon nanotubes and semiconducting carbon nanotubes from bundled carbon nanotubes; and obtaining of metallic single-walled carbon nanotubes separated at high purity through the above method. Metallic single-walled carbon nanotubes are dispersed one by one from bundled carbon nanotubes not only by the use of a difference in interaction with amine between metallic single-walled carbon nanotubes and semiconducting carbon nanotubes due to a difference in electrical properties between metallic single-walled carbon nanotubes and semiconducting carbon nanotubes but also by the use of the fact that an amine is an important factor in SWNTs separation. The thus dispersed carbon nanotubes are subjected to centrifugation, thereby attaining separation from non-dispersed semiconducting carbon nanotubes.