The corrosion and odor caused by hydrogen sulfide formation are serious problems in sewer operations, and the cost to prevent these problems is high. Understanding the sulfur cycle mechanism and controlling the sulfur cycle in sediment biofilm are essential to solve these problems. In this review, the reaction mechanisms of the sulfur cycle in sediment biofilm in sewer systems revealed by using in situ microelectrode measurements and molecular biological technologies are summarized. The results indicated that the profile of the reaction process of the sulfur cycle in sediment biofilm was primarily affected by the substrate concentration change in the liquid phase and the various substrate penetrations in sediment biofilm. The biological community's distribution and shifting of sulfate reduction bacteria and sulfide oxidation bacteria across the sediment biofilm were in response to the substrate change of the microenvironment in sediment biofilm. The influence of flow fluctuation on the profile of the sulfur cycle in the sediment biofilm of field sewers, the advantageous biological techniques of pyrosequencing and metagenome analyses combined with novel in situ microelectrode measurements, and the new concept model-related control technology of the sulfur cycle in sediment biofilm should be promoted in future studies.