Beishan area which is located in parts of the North China Plate intersection , Tarim plate and Kazakhstan sector has strongly tectonic - magmatic. LA-IC-MS dating for zircon separtated from the Jiaochgou quartz diorite plutons indicates that the plutons formed at 306.3±1.2Ma . Lithological and geochemical analysis show that the plutons withing I-type granite characteristics belong to middle-K tholeiitic and calk - alkaline series, and are enriched in large ion lithophile elements ( LILE) such as Rb, Sr and K,and depleted in high field strength elements ( HFSE) such as Nb, Ta, P and Ti.Quartz diorite has weak negative Eu anomalies (δEu of 0.80~0.93 , with an average of 0.88 ) with low total REE ( average of 81.01 × 10-6), and the more obvious LREE fractionation ((La / Yb) N changes at 3.40~4.77 , with an average of 4.06; (La / Sm) N changes in 1.88~2.57 , with an average of 2.24; (Gd / Yb) N changes in 1.16~1.32 , with an average of 1.26 ) . Geochemical compositions also show that the plutons are characterized by subduction genesis and the tectonic setting are continental margin arc. This set of rocks form late Carbonifous magmatic arc, presence of which may be related to the southward subduction of Hongshishan ocean slab by analysing regional tectonic evolution.