A cathode of a lithium battery includes a composite film. The composite film includes a carbon nanotube film structure and a plurality of active material particles dispersed therein. A method for fabricating the cathode of the lithium battery includes the steps of (a) providing an array of carbon nanotubes; (b) pulling out, by using a tool, at least two carbon nanotube films from the array of carbon nanotubes to form a carbon nanotube film structure; and (c) providing a plurality of active material particles, dispersing the active material particles in the carbon nanotube structure to form a composite film, and thereby, achieving the cathode of the lithium battery.