Disclosed is a method of fabricating a nano-tube that enables shortly cutting off said nano-tube without deteriorating said same and that when said nano-tube is used as said emitter can provide an improved flat-ability of said surface of said emitter, a method of manufacturing a field-emission type cold cathode that can provide an improved flat-ability of said surface of said emitter and that resultantly can cause an emission of a uniform, stable high-emission electric current, and a method of manufacturing a display device that includes a method of fabricating a nano-tube and/or a method of manufacturing a field-emission type cold cathode. The method of fabricating a nano-tube according to said present invention includes said step of radiating ions 2 onto a nano-tube 1 and said step of oxidizing said nano-tube 1.