The present invention relates to a carbon structure, which can stably support a high content of sulfur in pores and has excellent electrical conductivity properties, wherein the carbon structure is a polyhedron, of which the center on at least one side is concave, and is a highly graphitized nitrogen-doped porous carbon structure. Therefore, the stability of lithium-sulfur batteries can be improved by effectively suppressing a shuttle phenomenon occurring during an electrochemical reaction of lithium-sulfur batteries containing, as a cathode active material, the carbon structure supporting sulfur as well as minimizing the volume change resulting from sulfur and reduced lithium sulfide.
