Sr  = 0.7090 ~0.7092, εNd(t) = -15.62~-16.41). By integrating the geological and geochemical data, and by comparing them with the related rocks extensively, this pa per reaches the conclusion that the Qibaoshan pyroxenemonzonite is originated from partia l melting of the enriched mantle and the source region may contain both EMⅠ and EMⅡcomponents.