The lithium-sulfur battery system is considered to be a promising nextgeneration battery system due to its ultra-high theoretical energy density. However, there are still many technical challenges in the lithium-sulfur battery system, especially in the positive electrode part, and the development of highperformance positive electrode materials has become an important research direction for the lithium-sulfur battery system. This article briefly introduces carbon-based sulfur-carrying composite materials such as porous carbon,carbon nanotubes and graphene, and other types of non-carbon-based sulfur-carrying materials, and analyzes the action mechanisms of these materials in lithium-sulfur battery systems. At the same time, the technical challenges in cathode parts of lithium-sulfur batteries are discussed, such as poor cycle performance caused by the shuttle effect of polysulfides, poor conductivity and low sulfur utilization due to the insulation of elemental sulfur and its compounds, low volume energy density caused by low sulfur loading, and volume expansion in elemental sulfur discharge, and the corresponding strategies and research progress are summarized. Finally, it is expected that high-performance carbon-based materials will continue to be the research focus of the commercial development of lithium-sulfur battery cathode materials due to their low price and excellent performance.