lang="EN-US">The Xiongcun porphyry copper-gold metallogenic ore concentration area is located in the north of the middle Gangdise orogenic belt. No. I, II and III main ore bodies of Xiongcun area are hosted in ore-bearing porphyries and tuff along the contact zone. This paper mainly studied geochemistry of mineralized tuff in Xiongcun No. I ore body. The mineral assemblages of the source region include hornblende, plagioclase and minor garnet. Mineralized tuff, ore-bearing porphyry and metallogenesis belonged to the same volcano- magma-fluid system. The mineralized tuff provided mainly external factors for the mineralization, acted as an important ore-controlling condition and also serves as an important ore-prospecting geological condition.