Novel mesoporous carbon materials (MCMs) with excellent electron conductivity and high surface area are successfully synthesized from waste litchi shells. The as-prepared MCMs possess a narrow pore size distribution (0.5–2.0 nm) and exhibit similar electron conductivities to conductive carbon black (Super P, Timcal). Because of the unique properties of MCMs, they are used as host matrixes to encapsulate sulfur for lithium-sulfur cathodes. The obtained MCMs-sulfur (MCMs-S) composite cathodes deliver a high initial specific capacity of 1667 mAh g−1. Moreover, 300 °C treated MCMs-S composite cathode shows a more stable discharge capacity than the untreated MCMs-S composite cathode, it remains 612 mAh g−1 after 200 cycles at a high current density of 0.5 C.