Abstract: A carbon nanotube composite material contains a carbon nanotube and a continuous layer of a metal covering the inner surface of the carbon nanotube. It is produced by forming a metallic matrix layer and treating the metallic matrix layer to form plural nanoholes in the metallic matrix layer to thereby form a nanohole structure, the nanoholes extending in a direction substantially perpendicular to the plane of the metallic matrix layer; forming carbon nanotubes inside the nanoholes; and covering inner surfaces of the carbon nanotubes with a continous layer of a metal. It has a well controlled small size, has excellent and uniform physical properties, is resistant to oxidation of the metal with time, is highly chemically stable, has good durability enabling repetitive use, has good coatability, high wettability and dispersibility with other materials, is easily chemically modified, is easily handled and is useful in various fields.