A method of manufacturing carbon nanotubes that is capable of growing carbon nanotubes on a substrate by a CVD method without giving rise to residual carbon impurities is provided. The method of manufacturing carbon nanotubes according to the present invention is a method in which carbon nanotubes are grown on a substrate by a chemical vapor deposition (CVD) process using a reaction gas containing a compound for the carbon source, wherein a compound having a carbon skeleton and a functional group which is effective for removing carbon impurities that deposit during the growth of carbon nanotubes is used as the compound for the carbon source.