Altay granulite (AG), which represents the product of high-grade metamorphism in the lower crust, was newly found in the Wuqiagou area, Fuyun County in the Altay orogenic belt, Northwest China. It is composed mainly of hypersthene, augite, basic plagioclase, amphibole and brown biotite. Its mineral compositions of amphibole and biotite are rich in Mg/(Mg+Fe2+) and Ti. Geochemically, the AG is enriched in Mg/(Mg+Fe2+) and A12O3, and poor in CaO, with depletion of U, Th, K and Rb contents. Furthermore, geochemical data reflect that the protolith of the AG is igneous-genetic calc-alkaline basalt formed under an island arc environment. The AG has ZREE of 92.38-96.58 ppm and enriched LREE model with weak positive Eu anomaly of 1.09-1.15. In the MORB normalized spider diagram, the AG shows tri-doming pattern with a strong negative Nb anomaly and medium negative P and Ti anomalies, reflecting that the AG has tectonic relation with subduction or subduction-related materials. The P-T conditions of peak metamorphi