The increasing demand for energy requires development of high-performance energy storage devices that provide superior properties than the traditional Li-ion batteries. In the screening of alternative chemistries, Lithium-Sulfur (Li–S) batteries are one of the most promising candidates among rechargeable battery systems due to its low cost, high energy density, and high theoretical capacity. However, there are still some limitations that need to be overcome before Li-S batteries are viable for commercialization. One of the main drawbacks of this technology is the “shuttle” effect - migration of soluble polysulfide species from the cathode to the anode, which leads to parasitic reactions at the Li anode that yields a passivation layer that will lower the performance of the battery. In addition, the use of liquid organic electrolytes rises safety concerns due to their flammability. Unlike organic electrolytes, solid-state electrolytes (SSEs) are nonflammable and have the potential to suppress dendrite formation, improve battery lifetime, and enable the use of Li-metal anodes, which would increase considerably the energy density. However, before practical applications of SSEs with metal anodes, it is crucial to gain insights of the stability of the SSE/Li-metal interface. In this work, we use density functional theory (DFT) and ab initio molecular dynamics (AIMD) simulations in order to study the SSE/Li-metal interface. To learn more about the interfacial chemistry, we selected Li₂P₂S₆, Li₃PS₄, Li₇P₃S₁₁, and Li₁₀GeP₂S₁₂ as representative of the sulfide SSEs, which can exhibit high conductivity, good mechanical strength, and mechanical flexibility. Here, two low-index facets, (001) and (100), of the SSEs in contact with a Li electrode surface are studied. Reaction mechanisms, structure of fragments, and charge transfer evolution are examined and characterized in detail. Finally, some insights on the effect of a thin film of Li₂S (<1 nm) on the electrode/electrolyte interfacial stability are provided.