Lithium-sulfur　(Li-S)　batteries　have　been　demonstrated　as　one　of　the　promising　candidates　for　next-generation　energy-storage　devices.　However,　low　utilization　of　active　materials,　detrimental　shuttle　effect　of　lithium　pol-ysulfides,　and　sluggish　redox　kinetics　hamper　the　commercial　applications　of　Li-S　batteries.　Herein,　we　design　a　bilayer　functional　interlayer　composed　of　reduced　graphene　oxide/Se-doped　MoS2　(rGO/MoSSe)　layer　and　carbon　nanofiber　(CNF)　layer　(rGO/MoSSe@CNF)　for　high-performance　Li-S　batteries.　The　defective　structure　of　Se-doped　MoS2　significantly　improves　the　polysulfide　adsorption-catalytic　ability　due　to　the　exposure　of　more　active　sites　and　the　adjustment　of　local　electronic　structure.　Accordingly,　the　rGO/MoSSe　functional　layer　effectively　improves　the　electrochemical　reaction　kinetics　and　cyclic　stability.　In　addition,　the　CNF　layer　effec-tively　reduces　the　transport　resistance　of　Li+,　and　improves　the　reversible　capacity　at　high　current　densities.　The　Li-S　coin　cell　with　rGO/MoSSe@CNF　interlayer　delivers　a　remarkable　reversible　specific　capacity　of　922.4　mAh　g-　1　after　140　cycles　at　0.2　C　and　a　slow　capacity　decay　rate　of　0.057%　per　cycle　over　1000　cycles　at　1　C.　Moreover,　the　Li-S　pouch　cell　with　rGO/MoSSe@CNF　interlayer　at　sulfur　loading　of　3　mg　cm-2　can　maintain　a　reversible　specific　capacity　of　706.2　mAh　g-　1　after　the　rate　test　and　175　cycles　at　0.2　C.