High-energy-density lithium-sulfur (Li−S) batteries hold promise for next-generation portable electronic devices, but are facing great challenges in rational construction of high-performance flexible electrode and innovative cell configuration for actual applications. Here we demonstrated an all-MXene-based flexible and integrated sulfur cathode, enabled by three dimensional alkalized Ti3C2 MXene nanoribbon (a-Ti3C2 MNR) frameworks as S/polysulfides host (a-Ti3C2-S) and two dimensional delaminated Ti3C2 MXene (d-Ti3C2) nanosheets as interlayer on polypropylene (PP) separator, for high-energy and long-cycle Li−S batteries. Notably, a-Ti3C2 MNR framework with open interconnected macropores and exposed surface area guarantees high S loading and fast ionic diffusion for prompt lithiation/delithiation kinetics, and 2D d-Ti3C2 MXene interlayer remarkably prevents the shuttle effect of lithium polysulfides via both chemical absorption and physical blocking. As a result, the integrated a-Ti3C2-S/d-Ti3C2/PP electrode was directly used for Li−S batteries, without requirement of metal current collector, and exhibited high reversible capacity of 1062 mAh g-1 at 0.2 C, and enhanced capacity of 632 mAh g−1 after 50 cycles at 0.5 C, outperforming a-Ti3C2-S/PP electrode (547 mAh g−1) and conventional a-Ti3C2-S on Al current collector (a-Ti3C2-S/Al) (597 mAh g−1). Furthermore, all-MXene-based integrated cathode displayed outstanding rate capacity of 288 mAh g−1 at 10 C and long-life cyclability. Therefore, this proposed strategy of constructing all-MXene-based cathode can be readily extended to assemble a large number of MXene derived materials, from 60+ group of MAX phases, for applications such as various batteries and supercapacitors.