Hatu pluton in the southern margin of West Junggar invades into Early-Middle Devonian marine volcanic-sedimentary strata. The lithology of Hatu pluton is mainly composed of monzonitic granite, syenite granite and a small amount of alkali feldspar granite, which is an ideal object to study the tectonic setting of Late Carboniferous in West Junggar. The granites in Hatu pluton have high SiO2(72.06%-76.53%), Na2O+K2O(7.80%-8.57%)and Al2O3(12.55%-14.06%)contents, low CaO(0.20%-1.58%)and MgO(0.07%-0.42%)contents, with A/CNK(1.06-1.15)and A/NK(1.15-1.36)showing the characteristics of weakly peraluminous-strongly peraluminous granite. The granites have high total contents of REE((88.14-139.53)×10-6)and ratios of LREE/HREE((La/Yb)N is 3.04-6.50), and the chondrite-normalized REE pattern exhibits a typical right-dip “V” shape with a strong negative Eu anomaly, indicating that some plagioclases may be retained as a residue in the source area or there is the separation and crystallization of plagioclases. Meanwhile, the granites display significant enrichments of large ion lithophile elements(Rb, Th, U, K and Pb), relative enrichments of Zr and Hf, and depletions in Ba and Nb, especially Sr, Ti and P. The above characteristics demonstrate that Hatu pluton is a typical weakly peraluminous-strongly peraluminous A2-type granite. Combined with diagrams of major and trace elements, Hatu pluton in West Junggar is formed in a post-orogenic extension setting, and the petrogenesis is related to the juvenile crust that comprised both oceanic crust and island arc, which results from partial melting and fractionation under low pressure condition. [ABSTRACT FROM AUTHOR]