The Xiangcheng-luoji area straddles the border between western Sichuan and northwestern Yunnan. During Indosinian the Zhongza block ( i. e. Yidui island arc) and Yangzi block were welded to each other, as a whole they commenced the integrated evolution stage, with the Garze-Litang ocean being subducted beneath the Zhongza block. That is, after 254 -203Ma, a north-south striking Luoji-Xiangcheng Yanshanian peraluminous to meta- luminous A-type granitic belt developed during 76 ~ 85Ma prior to Himalayan orogenic collision at 65Ma, that comprises adamellite to granitcporphyry. It was an alkali-and aluminum-rich, and water-lack A-type granite, which derived from the continental crust formed from an island arc by island arc mag- matism or abnormal crust by a continental collision cycle ( mantle-derived magmatic rock, collision orogeny and crustal thickening). The strong copper and molybdenum polymetallic mineralization occurred in the belt, forming mainly thin vein ehalcopyrite mineralization in the hornfcls zone of the outer margin of magmatic intrusions with molybdenite in briquets with concentration; molybdenite mineralization forming molybdenite quartz veins, sparsely coarse crystal and disseminated molybdenitc in alteration granite in the middle of that; and 3 types of quartz-molybdenite vein mineralization occurred in the fraclutes.