A metamorphic unit, consisting of amphibolites interlayered with felsic gneisses, is exposed on Zabargad Island, in tectonic contact with mantle-derived peridotites. The amphibolites contain relicts of igneous pyroxenites and gabbros which have recrystallized into mafic granulites. The chemistry of the gabbros-pyroxenites' primary assemblage (Al-augite ± Al-orthopyroxene + kaersutitic pargasite ± plagioclase) suggests that the gabbro-pyroxenites are remnants of a basic layered complex which crystallized at pressures not lower than 9–10 kbar and probably not higher than 12–13 kbar. The felsic gneisses were originally made of quartz + plagioclase + orthopyroxene ± garnet ± clinopyroxene ± magnesiohastingsite, an assemblage characteristic of high pressures (− 5–12 kbar) garnet granulite facies. The high- P tonalitic-trondhjemitic composition of some of the gneisses suggests they were originally part of the lower continental crust, an interpretation supported by the presence of characteristic zircon crystals with ovoidal morphology. The association of granulitic gneisses with high- P gabbroic rocks suggests that the lower continental crust was intruded by basaltic magmas. The pyroxenite-gabbro complex underwent deformation when still hot, followed by recrystallization at P of about 5–6 kbar. During this event, breakdown of the Al-pyroxenes under hydrous conditions resulted in granulitic Al-poor pyroxenes + pargasitic hornblende + plagioclase assemblages. Both the mafic and sialic granulites subsequently underwent further decompression under increasing fluid partial pressure and oxygen fugacity, which resulted in widespread amphibolization of the rocks in the presence of relatively high- T, chlorine-rich, metasomatic fluids. The resulting assemblage Mg-hornblende + plagioclase + ilmeno-hematite ± sphene ± quartz suggests T of 600–700°C, P tot < 2 kbar and high ƒO 2 . Finally, rising fluid partial pressure leads to breakdown of Mg-hornblende and crystallization of metasomatic phases such as alkali-richer, alumina-poorer Mg-hornblende, actinolite. Cl-biotite, Cl-scapolite and Cl-apatite. The Zabargad metamorphic unit probably results from underplating of the lower continental crust by basic magma intrusions before and during the early stages of rifting in the central Red Sea. Subsequently, the lower crustal gabbro-gneiss complex was subjected to a number of retrometamorphic events under decreasing P- T conditions, probably related to progressive uplift during rifting and crustal thinning. The last, low- P metasomatic event is probably related to the final stages of the emplacement of Zabargad Island.