The volcanic rocks in Linzizong Group are developed in the Gangdise belt of Tibet, and can reflect the important information of Neo-Tethys from its subduction to the India-Asia collision. The Xingaguo area is located in the northern middle part of south Gangdise, Tibet, lying to the south of Luobadui-Milashan Fault. The volcanic rocks in Dianzhong Formation consist of rhyolitic detritus crystal tuff, and are distributed in a limited area in the north of the ore district. The volcanic rocks in Dianzhong Formation from Xingaguo are composed of rhyolitic detritus crystal tuff and are distributed in the northern area, with the exposed area being small. Chemical analyses show that the volcanic rocks in Dianzhong Formation have high SiO₂ (SiO₂=75.09%~78.10%), low alkali (K₂O+Na₂O=4.84%~6.52%), and low Mg (MgO=0.24%~0.37%), with peraluminous nature (A/CNK=1.02~1.75); they are characterized by LREE enrichment and obvious REE differentiation, with weak positive and negative Eu anomalies (δEu=0.76~1.15); they are enriched in LILEs (Rb, Th, U and K), depleted in HFSEs (Nb, Ta, P and Ti), and obviously depleted in Ba and Sr, thus belonging to calc-alkalic and peraluminous series and having the characteristics of continental margin arc volcanic rocks. The LA-MC-ICP-MS zircon U-Pb chronology indicates that the volcanic rocks in Dianzhong Formation were emplaced at 70.89±0.31 Ma, which is the oldest age for the volcanic rocks in Dianzhong Formation, and has ¹⁷⁶Hf/¹⁷⁷Hf values in the range of 0.282 820~0.282 939, εHf(t) values in the range of +3.2~+7.4 and single-stage model ages (t_DM) between 662 and 930 Ma. The volcanic rocks in Dianzhong Formation from Xingaguo area were formed in a tectonic environment of ocean subduction, mainly derived their materials from the mantle components, and contaminated crustal material in the process of magma rising.