The Late Carboniferous Liushugou Formation in the Bogda orogenic belt of the Eastern Tianshan Mountains is a bimodal volcanic rock composed of basalt and rhyolite, which was formed in the Late Carboniferous. Its SiO₂ content is between 46.18%~46.56% and 76.06%~76.25%, with obvious Daly component discontinuity. Basalt is characterized by rich sodium and poor potassium. Its TiO₂, Al₂O₃, Cao and MgO values are high, ΣREE is 75.54×10^-6~80.22×10^-6, LREE/HREE is 3.00~3.12, with enrichment of Ba,Rb and other large-distance lithophile elements (LILE) and incompatible elements (P,K), and relative loss of Ti, Ta, Nb and other high field strength elements (HFSE) and incompatible elements (U,Th). The Na₂O/K₂O ratio of rhyolite is 0.32~0.36, suggesting low titanium (Ti) and low magnesium (Mg) rhyolite. The ∑REE is 520.72×10^-6~595.26×10^-6, and the LREE/HREE is 5.60~6.53, which shows the enrichment of Rb, Th, K, La, Ce, Zr, Hf, Sm and other elements and the loss of Ba, U, Ta, Nb, Sr, P and Ti elements. The bimodal volcanic rocks of Liushugou Formation were formed in a continental rift environment with intraplate genetic characteristics. Basalts may be the product of partial melting of the transition phase from depleted spinel mantle peridotite to garnet mantle peridotite, which was contaminated by crustal materials. Rhyolites have typical geochemical characteristics of A-type granites.