To further investigate the provenance, weathering, and tectonic setting of the Late Ordovician—Early Silurian black shale in the southern margin of the Upper Yangtze area, this study systematically sampled typical outcrops, analyzed the geochemical characteristics of major, trace and rare earth elements in the Wufeng—Longmaxi Formations shale, and explored its geological significance.Methods: By analyzing the major, trace, and rare earth elements of 22 samples from the Wufeng—Longmaxi Formations shale in the outcrops of the southern margin of the Upper Yangtze area, this study reconstructed ancient weathering intensity and paleoclimate conditions, unveiled the provenance and tectonic setting, and investigated the shale formation environment and processes. These findings provide compelling geochemical evidence to support further exploration and development of the Wufeng—Longmaxi Formations shale in the Upper Yangtze area.Results: The black organic- rich shale of the Wufeng—Longmaxi Formations in the southern margin of the Upper Yangtze area exhibited characteristics such as low abundance of high field strength elements and enrichment of the large ion lithophile elements akin to the Upper Continental Crust. The ∑REE values ranging from 103. 66×10-6~295. 98×10-6, with an average of 180. 57×10-6, indicated generally high rare earth element content. The standardized distribution pattern of the rare earth elements closely resembled that of the Upper Continental Crust, demonstrating a ‘V’ type pattern with rightward skew, enrichment of light rare earth elements, flat heavy rare earth elements, clear differentiation between light and heavy rare earth elements, and a distinct negative Eu anomaly. Moreover, the contents and ratios of characteristic trace and rare earth elements, such as La, Ce, La/Yb, and Sc/Cr, closely align with the characteristic values of the Passive Continental Margin. The ICV values ranging from 0.55 to 14. 1, with an average of 2. 28, and the Zr/Sc versus Th/Sc ratios suggested that the source was the result of initial rapid sedimentation of the tectonic belt, without indications of sedimentary recycling. Furthermore, the lower CIA values (ranging from 54. 89 to 71. 61, with an average of 65. 27), A—CN—K and K2O/Al2O3 versus Ga/Rb ratios suggested minimal impact from chemical weathering on the provenance, and indicated a cold and dry sedimentary environment. The high contents of K2O, Rb, Al2O3/TiO2, and the negative Eu anomaly pointed toward a provenance dominated by felsic igneous rocks and acidic geological bodies such as granites. Conclusions: Based on the discriminant diagram of provenance and tectonic setting, it was inferred that the Wufeng—Longmaxi Formations shale in the southern margin of the Upper Yangtze area originated in the Passive Continental Margin. The predominant provenance was the early Neoproterozoic platform caprock of the Kangdian ancient land to the west, with partial contributions from the Qianzhong uplift, alongside the inflow of intermediate—acid volcanic materials from the southeastern Yangtze area.