Lithium-sulfur batteries (LSB) with high theoretical specific capacity/energy density still face some practical challenges, for instance shuttle effect, sluggish redox kinetics and corrosion of Li anode, which leads to rapid capacity decay. To overcome these challenges, herein, a porous and flexible sulfur host composed of interconnected Co9S8 nanosheets in-situ grown on carbon cloth surface was constructed by a one-pot solvothermal method and applied as binder-free self-supporting electrode of LSB. The interconnected carbon fiber skeleton and highly conductive Co9S8 nanosheets can provide abundant electron-transport channels to ensure excellent electric conductibility for electrode. Meanwhile, the abundant adsorption and catalytic sites provided by Co9S8 nanosheets can effectively inhibit dissolution of polysulfides and improve conversion kinetics of polysulfides, effectively suppressing “shuttle effect” and protecting Li anode. The interconnected Co9S8 nanosheets can also offer adequate void to facilitate penetration for Li2S6 solution/electrolyte, accelerate lithium-ion diffusion and accommodate volume expansion of sulfur, thus ensuring high sulfur utilization and remarkable cycle stability of electrode. The Co9S8-CC/Li2S6 electrode achieves impressive lithium-storage performance, including high discharge capacity (1315.1 mA h g− 1, 0.1 C), excellent rate capability (872.4 mA h g− 1, 2 C) and outstanding cyclic stability (decay of 0.02%/cycle over 1500 cycles, 2 C). Under a high sulfur-loading of 6.2 mg cm− 2, the Co9S8-CC/Li2S6 electrode still delivers high discharge capacity (1115.1 mAh g− 1, 0.1 C) and good cycling stability (decay of 0.129%/cycle during 200 cycles, 0.5 C). This study offers insights for rational designing and structure engineering of self-supporting metal sulfide based composite host for high-performance LSB application.