Carbon nanostructure, method for producing carbon nanostructure, and production device for same

The invention provides a carbon nanostructure, a method for producing carbon nanostructure, and a production device for same. The method for producing a carbon nanostructure comprises a preparation step (S10) and oxidation step (S20) for preparing a base body, and a step (S30) for growing a carbon nanostructure. In the steps for preparing a base body, a base body is prepared in which at least some of the contact sites or integrated sites of a catalyst member and a separation member have been oxidized. In step (S30), a carbon nanostructure is grown in the separation interface region of the catalyst member and separation member. Step (S30) includes at least one of a step for providing raw material gas locally to a part facing the separation interface region where the carbon nanostructure grows in the catalyst member, and a step for locally heating the separation interface region. This makes it possible to provide a long carbon nanostructure having suppressed occurrence of bending and the like, a method for producing this carbon nanostructure, and a production device to be used in the method for producing this carbon nanostructure.