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The Um Khariga metavolcanics (UKMV) represent one of the biggest metavolcanic suites in the central Eastern Desert of Egypt. Based on field, petrographic and geochemical considerations the UKMV range in composition from basalts to rhyodacites. Geochemically, the volcanics have a strong calc-alkaline to weak tholeiitic affinity, exhibit enrichment in LILE, depletion in HFSE and have negative Nb anomalies, together with high Zr/Y ratios. These features are characteristic for basalts from active continental margins. The low Mg# (45), Ni (57 ppm) and Cr (113 ppm) contents of the Um Khariga basalts, together with the curvilinear trends displayed by some element variations indicate that the rocks evolved by fractional crystalization processes. The evolution of the UKMV andesites and rhyodacites can be modelled by separation of 29% and 34% from basaltic-andesites and andesites parents, respectively. The subduction zone is the dominant source of Ba, Rb, Sr, K and P for the genesis of the Um Khariga basalts, while Nb, Zr, Ce, Ti and Y are inherited from small scale partial melting of the subducted slab. The UKMV most probably originated in a convergent plate margin setting, possibly a primitive continental are, similar to many contemporaneous calc-alkaline convergent plate margin basalts.