Argyrodite-based sulfide electrolytes have received considerable attention in all-solid-state lithium metal batteries owing to their high ionic conductivity and good mechanical property. However, the reactivity between sulfide electrolytes and lithium anode leads to continuous interfacial reactions and dendrites growth, which severely hinders their practical applications. We propose an electron localization strategy by modulating the d-p orbital hybridization within the PS4 tetrahedral structure of Li6PS5Cl through homogeneous incorporation of yttrium (Y) and oxygen (O). The introduction of Y strengthens the Madelung energy with sulfur (S) atom and induces the electronic localization of S atom, which suppresses the interaction between lithium metal and S atom of the tetrahedron. The air-stability is also enhanced due to oxygen introduction. Furthermore, the in-situ formation of Li2O interphase acts as a protective barrier, synergistically mitigating the interfacial reactions between lithium metal and Li6PS5Cl. The Li symmetric cell with the modulated Li6PS5Cl electrolyte achieves stable lithium plating/stripping for over 4800 h. The all-solid-state batteries with LiCoO2/Li-In electrode display a remarkable long cycle performance with 100% retention after 1300 cycles at 0.5 C. This study presents a distinct strategy that employs the electron localization driven by modulating orbital hybridization to achieve ultra-stable interface in sulfide-based all-solid-state lithium batteries.