<p>The Bijiawan Pb-Zn deposit is situated within the metallogenic belt of the Western Qinling, China, yet its genesis remains ambiguous. In this study, LA-ICP-MS was employed to analyze sphalerite ore samples, revealing that sphalerite in the deposit is notably enriched in Cd and Fe, and moderately enriched in Mn and Ga. The ore-forming temperatures for the limestone-hosted sphalerite range from 150℃ to 168℃, while those for the phyllite-hosted sphalerite range from 232℃ to 239℃. Trace element analyses indicate several key substitution mechanisms: Zn²⁺ ↔ Fe²⁺ and Zn²⁺ ↔ Cd²⁺, reflecting coupled substitution between Cd and Fe; Fe²⁺ + Mn²⁺ → 2Zn²⁺, suggesting an interaction between Fe and Mn; a coupling substitution of 2Zn²⁺ ↔ Ag⁺ + Sb³⁺ between Ag and Sb; and, specifically in the phyllite-type sphalerite, a substitution of Sb³⁺ + Cu⁺ → 2Zn²⁺ between Sb and Cu. Trace element discrimination diagrams show a strong affinity of both sphalerite types with Mississippi Valley-type (MVT) Pb-Zn deposits. The Zn/Cd ratio further suggest a relationship to metamorphosed sedimentary deposits and stratiform deposits within carbonate rocks, with the majority of data points falling within the MVT deposits region on trace element diagrams. Sulfur isotope analysis reveals average δ³⁴S values of 15.95‰ for limestone-hosted sphalerite and 18.75‰ for phyllite-hosted sphalerite. The sulfur is primarily derived from the reduction of seawater sulfate or strata-bound sulfate, with thermochemical reduction processes likely being the dominant mechanism. In conclusion, the Bijiawan Pb-Zn deposit is classified as a MVT deposit.</p>