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Zircon Hf isotopic compositions for Neoproterozoic igneous rocks in the Central Eastern Desert of Egypt are presented and interpreted. The Humr Akarim (633 +/- 7 and 603 +/- 9 Ma)-Humrat Mukbid (625 +/- 8 and 619 +/- 8 Ma) plutons are Early Ediacaran post-collsional subsolvus granites. Their zircon ages range from 0.57 to 0.71 Ga, with high positive epsilon Hf(T) values of +4.0 to +11.9. Hf model ages (Hf-T-DM(c)) of 0.81-1.3 Ga, are close to the U-Pb crystallization ages. These isotopic characteristics, along with published whole-rock Nd isotopic data, indicate that the protoliths were juvenile. The Wadi Kareim and Wadi El-Dabbah metavolcano-sedimentary rocks are Cryogenian (similar to 750 Ma) arc-related metabasalts, meta-andesites and meta-tuffs. Their U-Pb zircon age populations range between 0.7-0.9, 0.9-1.5 Ga and 2.0-3.0 Ga. The youngest group represents magmatic zircons in the metavolcanics or reworked Neoproterozoic rocks in the metasediments. The 0.9-1.5 Ga and 2.0-3.0 Ga age groups are similar to those in pre-Neoproterozoic rocks that surround the Arabian-Nubian Shield and represent inherited or older detrital grains. The highly variable epsilon Hf(T) values (+23.5 to -35.0) and Hf-T-DM(c) ages (0.78-3.8 Ga) of Neoproterozoic zircons indicate that at least some of these magmas interacted with a pre-Neoproterozoic crustal source. (C) 2013 Elsevier B.V. All rights reserved.