Carbon nanotube and fuel cell using the same

A carbon nanotube for a catalyst support is provided. The carbon nanotube has a length of about 300nm or less, and an aspect ratio of about one to about fifteen. The carbon nanotube has a good broad surface area and better electric conductivity and is opened at both ends, thereby allowing impregnation by a metallic catalyst into the inner side of the carbon nanotube. Such catalyst impregnated carbon nanotube has a broad effective specific surface area, and thus, has an improved efficiency of catalyst utilization, can reduce an amount of the catalyst used and can efficiently diffuse a fuel. Accordingly, when catalyst impregnated carbon nanotube is used in a fuel cell, etc., improvements can be made in the pricing, power density of an electrode, and energy density of a fuel cell.