Herein an effective way for construction of all‐solid‐state lithium‐sulfur batteries (LSBs) with sulfur/reduced graphene oxide (rGO) and Li9.54Si1.74P1.44S11.7Cl0.3 solid electrolyte is reported. In the composite cathode, the Li9.54Si1.74P1.44S11.7Cl0.3 powder is homogeneously mixed with the S/rGO composite to enhance the ionic conductivity. Coupled with a metallic Li anode and solid electrolyte, the designed S/rGO‐Li9.54Si1.74P1.44S11.7Cl0.3 composite cathode exhibits a high specific capacity and good cycling stability. A high initial discharge capacity of 969 mAh g−1 is achieved at a current density of 80 mA g−1 at room temperature and the cell retains a reversible capacity of over 827 mAh g−1 after 60 cycles. The enhanced performance is attributed to the intimate contact between the S/rGO and Li9.54Si1.74P1.44S11.7Cl0.3 electrolyte, and high electrical conductivity of rGO and high ionic conductivity of the solid electrolyte.