The information concerning dissociative adsorption of H2 S on Li surface is inadequate and the mechanistic insight for its complete dissociation is yet to be explored. The present investigation aims to scrutinize the dissociative adsorption of H2 S on Li(110) surface using density functional theory calculations. The climbing image nudged elastic band calculation was employed to unveil the relative energy profiles for S-H dissociation. To elucidate the components of interaction energy responsible for stabilizing the adsorbed moieties on the surface, periodic energy decomposition analysis was performed. A Car-Parrinello molecular dynamics (CPMD) simulation was performed to understand the dynamic behaviour of H2 S on Li(110). Results vividly demonstrates: (i) partially dissociated product with perpendicular S-H is comparatively stable than the parallel SH, (ii) completely dissociated moieties H/H/S are the most stable among all, (iii) dissociation of first S-H is barrierless and the second S-H dissociation is a low energy barrier reaction, (iv) complete dissociation of H2 S occurs in a stepwise manner, (v) orbital and electrostatic contributions of the interaction energy plays a vital role in stabilizing the dissociated moieties, and (vi) stepwise dissociation of H2 S was further reinforced by CPMD.