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It is shown that sandstones of the Upper Permian-Lower Triassic molasse sequence in the South Ural segment of the Uralian foredeep are graywackes with clasts of predominant cherts, quartzites, quartzite-type sandstones, and less common limestones, polymictic sandstones, basic and silicic magmatic rocks, and serpentinites. Psammites are cemented by corroded calcite; sandstones are frequently enriched in zeolites (analcime and heulandite). According to Dickinson’s concept, the proportions of different types of detrital grains suggest that the considered psammites were formed by the disintegration of rocks of recycled orogen and fold-thrust belt. As compared to the Phanerozic sandstones, graywackes of the molasse have lower mean contents of SiO2, TiO2, Al2O3, Fe2O3, K2O, and P2O5 but similar to 1.4 to similar to 3.8 times higher contents of MgO, CaO, MnO, and Na2O. The mean contents of most trace elements in the Upper Permian and Lower Triassic sandstones are lower than in rocks of the upper continental crust. The Th/Sc and Zr/Sc values indicate their predominant petrogenic character. The total REE contents in the studied sandstones vary from 21 to 100 ppm. The highest mean total REE and La-N/Yb-N values were found in the psammites of the Tatarian stage. This presumably indicates that source areas at that time contained abundant silicic magmatic rocks. Judging from some geochemical features of sandstones, the clastic material was transported over a relatively short distance and did not experience significant chemical differentiation. Data points of psammites in the diagrams Q(t)/(F + R)-Q(p)/(F + R) and (Al2O3 + K2O + Na2O)/SiO2, as well as sufficiently low values of the hydrolyzate module, indicate their formation under arid climatic conditions, which is fairly consistent with geological data. Molasse sandstones of the South Ural segment of the Uralian foredeep are one of few geological objects, which demonstrate a good agreement between geological data and reconstructions derived from lithogeochemistry.