The petrogenesis of the Luobusa mantle peridotites (Southern Tibet) has remained unclear. Here, a suit of the Luobusa peridotites is presented to trace their petrogenetic history. These peridotites contain protogranular lherzolites, porphyroclastic harzburgites and equigranular harzburgites, which span most compositional spectrum of global mid-ocean ridge peridotites (MORP) and supra-subduction zone peridotites (SSZP). The petrogenesis of these peridotites was linked to a two-stage mantle evolution from the MOR to the SSZ. The lherzolites are least refractory with comparable compositions to the MORP such as high whole-rock Al₂O₃ (0.90–1.72 wt%) and low spinel Cr^# (20–40), which represent mantle residues after 8–16 % near-fractional melting of a depleted MORB mantle (DMM) source beneath anhydrous MOR. The porphyroclastic harzburgites are highly depleted with an SSZP affinity indicated by extremely low whole-rock Al₂O₃ (<0.50 wt%) and high spinel Cr^# (57–65). They represent residual mantle wedge fluxed by the slab-fluids above a subduction zone after subduction initiation. Their trace element compositions of clinopyroxenes are consistent with the additional 8–12 % flux melting of a depleted harzburgite source that previously experienced ∼ 10 % depletion of an initial DMM source. The equigranular harzburgites are characterized by the enrichments of Na, Cr, Ti and MREE in amphiboles and clinopyroxenes and Ti in spinels, which might result from the metasomatism of a slab-derived eclogite melt. Therefore, the heterogeneous Luobusa mantle peridotites in this study recorded a multi-stage tectonic evolution from the MOR to the SSZ.