Numerous lamprophyre dykes occur and cut through the Late Mesozoic granitic complexes in Taihang Mountains, North China Craton. These dykes are highly enriched in LIL elements such as Rb, Sr, Ba and K as well as light REE. The highly frac- tioned REE patterns and the regular variation in chemical and Nd-Sr isotope composition show that these lamprophyres were produced from the fractionation of the parent magma, and the ascending magma was contaminated by the lower crust. Most primitive lampro-phyres show low SiO2, high MgO and highly enriched isotope [εNd(120 Ma)=-8.3,ISr=0.705 2], indicating that the parent magma was derived from partial melting of the enriched continental lithosphere mantle. The mantle was enriched in the Middle Pro-terozoic, during when volatile-rich and low-density melts were released by asthenosphere interacting with the above lithosphere.