| Summary: | Prydz Bay is an important part of the Pan-African high-grade tectonic mobile belt. The focus of this investigation, by applying zircon LA-ICP-MS U-Pb geochronology, zircon Lu-Hf isotope systematics, and whole-rock geochemistry, is on Pan-African pegmatites in the Larsemann Hills of Prydz Bay, East Antarctica, their association with country rocks, and the formation conditions. Based on the obtained results, it is concluded that the pegmatites exhibit elevated levels of silica and alkali and possess peraluminous features. These pegmatites originated during the late Neoproterozoic–Early Cambrian (Pan-African) event, specifically in the D<sub>2</sub>–D<sub>4</sub> stages. The D<sub>2</sub> stage occurred between 546 and 562 Ma, followed by D<sub>3</sub>-stage pegmatites around 534 Ma. The pegmatites from the D<sub>2</sub>–D<sub>3</sub> stages are considered to originate from Paleoproterozoic crustal materials, while there are at least two phases of pegmatites in the D<sub>4</sub> stage (~517 Ma and ~521 Ma). The D<sub>4-1</sub> pegmatite (~521 Ma) suggested both Paleo–Mesoproterozoic crustal origin, perhaps connected to extension. The D<sub>4-2</sub> pegmatite (~517 Ma) originated from the crust layers. In the Larsemann Hills, Pan-African pegmatites formed in a recurring regime of tension. Therefore, the obtained data elucidate that a Pan-African stretching process might have occurred in Prydz Bay.
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