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The Wadi El-Hudi area, in the south Eastern Desert of Egypt, comprises a high-grade metamorphic complex of migmatite and biotite gneiss that host a garnet-bearing leucogranite body. This complex has been intruded later by post-orogenic pink granites. Gneisses and migmatites show obvious irregular layering, which lies concordently with the main foliation. The garnet-bearing leucogranite is a texturally heterogeneous small body (about 3 km(2)) that possesses a similar mineralogical composition to that of gneisses and migmatites. This mineralogical similarity, beside the presence of ubiquitous metasedimentary xenoliths of the same mineralogical composition as the migmatite, indicates a cogenetic relationship. Geochemically, the garnet-bearing leucogranite is strongly peraluminous (A/CNK > 1.1) with normative corundum ranging between 1.3% and 4.0%. Major and trace element contents show considerable variations related to textural and mineralogical heterogeneity. Most of the samples have low CaO (0.23-1.15%), Sr (26-183 ppm), Y (11-35 ppm) and Zr (10-48 ppm) and high Na2O (2.78-4.02%), Rb (67-118 ppm) and Rb/Zr (2-12). These data, together with the field and mineralogical observations, imply that the garnet-bearing leucogranites were formed by dehydration partial fusion of chemically immature pelitic materials. The high contents of Zr (154-766 ppm), Cr (60-70 ppm), Y (116-177 ppm) and LREE (La + Ce + Nd = 290-335 ppm) are explained, in some samples, by their being retained from refractory mineral phases where the solid residue did not completely escape. The garnet-bearing leucogranite was emplaced as a consequence of high-temperature metamorphism during a major collisional event in eastern Egypt, when a Pan-African terrane assembly was attached to the East Saharan Craton. The high-temperature metamorphism was induced by anomalously high heat influx to shallow crustal levels subsequent to collision and crustal thickening. (C) 2002 Elsevier Science Limited. All rights reserved.