The Cenozoic mantle xenolith bearing high-potassic basalts (7.1～23　Ma) distributed in western Qinling, western China are a window to probe the mantle composition and geodynamics beneath north-eastern margin of Tibetan Plateau. The chemical and carbon isotopic compositions of volatiles suggested that a recycled crustal component derived from the devolatilization of subducted oceanic plate or sedimentary rocks, which could be related to paleo-Tethyan oceanic plate or northern China Plate with Yangtze Plate subduction and collision under the system of India-Asia collision.