A number of small and medium Au and Cu deposits （occurrneces） were found in Guaizihu area， Inner Mongolia， and these deposits were accompanied by small granite strains （branch） in spatial terns. This paper， using petrogeochemistry method and combining the study of macropetrology in the field， revealed the internal relationship of magma source area qualities and mineralization. The results showed that Guaizihu granite belongs to high-K calc-alkaline series with peraluminous characteristics， relatively strong fractionation between light rare earth element（LREE） and heavy rare earth element（HREE）， and relatively enriched in LREE （（La/Yb）N=3.78～20.13）. ORG normalization of trace elements showed that the granites are enriched in large-ion lithophile elements（LILE） such as Rb，Ba，Th，K and depleted high field strength elements（HFSE） such as Nb、Ta、Sr、P . Guaizihu granite belongs to low Sr and low Yb type. The magmatic source is from lower crust volcanic rock. The magma formed in lower crust partial melting which is induced by the process of collision orogenic - crustal thickening. A series of evidence showed that the disappearing of ancient Asia ocean in the east of Central Asian orogenic belt， which is represented by Engel Usu ophiolite belt， occured at the end of the early Permian.