AbstractBesides lithium‐ion batteries, it is imperative to develop new battery energy storage system with high energy density. In conjunction with the development of Li‐S batteries, emerging sulfur‐containing polymers with tunable sulfur‐chain length and organic groups gradually attract much attention as cathode materials. This can avoid the problems that are impeding the development of the typical Li‐S batteries, such as volume expansion, active material dissolution, shuttle effect, and so on. This review aims to generalize the type of sulfur‐containing polymers and the working principles in Li‐S batteries. The sulfur‐containing polymers (R‐Sn‐R) with different sulfur‐chain length (n > 6, n ≤ 2, and 3 ≤ n ≤ 6) are summarized. It also discusses several organic groups such as phenyl rings, N‐heterocycles, and unique structure with cross‐linked networks and multi‐micropores skeleton. This review also explores other strategies of sulfur‐containing polymers in the rest of Li‐S batteries, providing a summary of the advantages of sulfur‐containing polymers, recent development, in‐depth discussion of the mechanism in Li‐S batteries, and organic group‐structure‐performance relationship. This review would have guidelines for future development of sulfur‐containing polymers in Li‐S batteries.image