The present invention relates to a carbon structure capable of stably carrying a high content of sulfur in pores and having excellent conductive characteristics, in which the carbon structure is a polyhedron, the center of at least one side of the polyhedron is concave, and the carbon structure is a highly graphitized nitrogen-doped porous carbon structure. Accordingly, stability of a lithium-sulfur battery can be improved by effectively suppressing a shuttle phenomenon occurring during an electrochemical reaction of the lithium-sulfur battery including a sulfur-bearing carbon structure as a positive electrode active material and minimizing a volume change caused by sulfur and reduced lithium sulfide.
