The invention relates to a method for producing single-wall carbon nanotubes. The method of the invention comprises the steps of (a) providing a plasma torch having a plasma tube with a plasma-discharging end; (b) feeding an inert gas through the plasma tube to form a primary plasma; (c) contacting a carbon-containing substance and a metal catalyst with the primary plasma at the plasma-discharging end of the plasma tube, to form a secondary plasma containing atoms or molecules of carbon and atoms of the metal catalyst; and (d) condensing the atoms or molecules of carbon and the atoms of the metal catalyst to form single-wall carbon nanotubes. Alternatively, steps (b) and (c) can be carried out by feeding an inert gas and an inorganic metal catalyst through the plasma tube to form a primary plasma containing atoms of the inorganic metal catalyst and contacting a carbon-containing substance with the primary plasma at the plasma-discharging end of the plasma tube, to form a secondary plasma containing atoms or molecules of carbon and the atoms of metal catalyst. An apparatus for carrying out the method according to the invention is also disclosed.