• A 3D porous graphene aerogel decorated with high exposure of anatase TiO 2 (001) nanoplatelets is prepared. • The TiO 2 (001) facet is highly matchable to graphene (002) lattice, thus facilitating their electronic transfer. • The in-site assembled TiO 2 @GA host exhibits superior sulfur-immobilized capability. • The tailored lithium-sulfur cell shows excellent performance. Resulting from the development of electric vehicles, high energy-density Li-S batteries have recently attracted ever-increasing attentions worldwide. However, continuous dissolution of cathodic sulfur and followed shuttle effect of polysulfides lead to very limited service lifetime for currently-applied Li-S batteries. Herein, a 3D porous graphene aerogel (GA) decorated with high exposure of anatase TiO 2 (001) nanoplatelets is proposed as robust host to immobilize cathodic sulfur. Compared with commonly used TiO 2 (101) nanoparticles, the TiO 2 (001) nanoplatelets have highly matched lattices with graphene (002) nanosheets, thus facilitating the electronic transfer. The in-site assembled TiO 2 @GA host exhibits superior sulfur-immobilized capability, which cannot only entrap sulfur by physical confinement, but also capture dissoluble sulfurous species by chemical bonding. The fabricated S@TiO 2 @GA cathode shows excellent electrochemical performance with high discharge capacity, superior rate capability, and durable cycling stability as well, supposed to be a promising cathode for high-performance Li-S battery applications. The in-situ assembled TiO 2 (001)@GA(002) host presents superior sulfur-immobilized capability. As a result, the tailored S@TiO 2 @GA cathode shows remarkably promoted electrochemical performance in the lithium-sulfur battery.