Abstract:The authors studied 439 zircon grains collected from Cishan biotite monzonite granite and found that most zircon grains keep perfect crystal forms, and that there exist corroded zircon crystals. Based on such evidence, the authors believe that Cishan granite is of magmatic origin.93 By comparing characteristics of zircon groups from three main types of gold_hosting granite, namely Linglong granite, Guojialing granodiorite, Kunyushan granite, the authors have also drawn the conclusion that, Cishan and Linglong granites are similar to each other in evolution. It is considered that, as Linglong granite was formed in Late Jurassic, Cishan granite must have also intruded in Late Jurassic. The TET curve of zircon from Cishan granite starts from metamorphic rock and migmatite region, and the low_temperature part is located in the crust origin region, suggesting that partial remelting of Jiaodong group led to the formation of Cishan granite. The crystallization temperature of zircon spanned a wide range from 800℃to 600℃, which implies the richness of water and the favorable condition for mineralization of Cishan granite. Nevertheless, due to its high emplacement position and weak oxidizing capacity, its mineralizing capability is lower than that of Linglong granite.